Why hold conferences in a resort town?

I cannot talk about general customs, but for whatever it’s worth, a major conference in my field is held in a ski resort, off-season. This has two advantages:

1. This is what the resort does to survive during the warm seasons. Therefore I presume that it may be a relatively cheap option.

2. Except for hiking, there is nothing to do there. With conferences held in cities, it often happens that attendants take some time off to do some sightseeing or similar. Here, getting to the next (touristically boring) city requires you to rent a car and takes one hour. Therefore, the conference gets more attention.

This is an example of a social norm, which is a kind of large-scale Nash equilibrium. Namely, there is no special justification for why academics benefit from the perk of being able to travel to attractive tourist destinations for their professional meetings, other than the fact that this is the norm that has developed historically, and once the norm has developed, it is stable against disruption, since no particular player in the game (in the sense of game theory) that is academia has an incentive to disrupt it. The only people who might object are funding agencies who may prefer if conferences were organized in drab, cheap locations, but if ever any such agency were to propose to cut off funding for conferences held in interesting places, the people being funded would cry out that this would hurt the competitiveness of their conferences relative to other similar conferences being organized by people funded by other more permissive funding agencies, and the reform would be scrapped. This is precisely the general dynamic at work that helps maintain many Nash equilibria/social norms.

That being said, the tradition of having conferences in nice places also benefits scientists, and therefore science, by allowing them to do their work in a pleasant environment that is conducive to stimulating creativity. Of course, people in other industries would also enjoy these sorts of conditions, but they can't all arrange them for themselves, so perhaps the right question to ask is not why academia can do it, but why other industries can't.

Another thought is that holding conferences in attractive tourist destinations also provides an economic stimulus of sorts to the travel and tourism industries of many countries, so may not be a bad thing, and by providing employment to multiple economic sectors it attracts political support that again makes it difficult to eliminate this particular "market inefficiency" (such that it is).

That differs a lot by discipline: in mine (sociology) the annual conferences of the different associations/societies/sections/etc. are typically hosted each year by a different university, and the conference takes place not in a resort or hotel but on campus. Only the really large conferences have to get creative in order deal with the large number of participants.

In my field (and the field I was in during my Ph.D.) important conferences are never held in small resort towns. So at the very least this is specific to some fields rather than others.

I think that generally this is a bad idea, since it discourages attendance by graduate students and interested members of the general public - and that the touristic/"vacationish" attractiveness of the experience to the people more central to the conference doesn't justify this. Also, if pricing is somehow an issue, you would think these conferences would be held on some university grounds, which I'm guessing should be cheaper.

As a young academic in a third-world/developing nation (albeit not one of the bottom tier nations), I can address another issue not yet covered by the answers thus far, that of profit.

Conferences in my field of study (STEM) and in my region of the world (Asia) tend to not just be in visit-able places (not necessarily resort towns though, depending on the country), and the recommended hotels also tend to be in tourist-y sections of the town. This serves several purposes:-

1. Availability of services/amenities suitable for travelling individuals (laundry services, cleaner restaurants, public transport and/or Uber etc.)
2. Greater access to tourist-friendly resources, such as a larger proportion of English-speaking locals outside the hotel/conference center/resort itself.
3. "Additional" services unique to the destination (or of high desirability), such as local exotic cuisine, massage parlours, or even accessibility to the local red-light districts (anecdotal based on a conference I've been involved in before).

All of the above matter because one of the reasons (arguably a primary reason) for holding conferences is to generate an income, and that income depends primarily on participants being willing to come and attend (especially participants from outside Asia from more prestigious institutes). A destination which is boring, while suitable (based on the other answers) for well-established conferences is actually a disadvantage for less well-established ones.

There are many possible reasons, depending on the field and the conference.

• Many resort towns are no more remote than most cities for international participants. Some major cities have better connections, but hosting conferences in them tends to be expensive.
• Hosting the conference at a university is usually the cheapest option, but suitable facilities are not always available.
• In fields with many conferences, the conferences have to compete for participants. An interesting location can attract more participants to the conference.
• While small conferences are generally run by volunteers, larger conferences may have to use paid help. Such services are often cheaper in resorts than in cities.
• A conference is supposed to bring people together. This works better if the participants cannot escape to other activities.
• Sometimes conference participants vote on the location of future conferences. As the alternatives are not necessarily known in advance, it can take very little to sway the opinion to support one location or another.
• Volunteer-run conferences often have a shortage of volunteers. If there is only one reasonable offer to host the conference, the volunteers effectively decide where the conference will be held.