The problem is, in a nutshell, parking.
Let's put it this way... we pulled up a list of
EVERY HOTEL IN CHATTANOOGA.
We looked at the prices, and crossed off anything that was too expensive (if I recall correctly, that meant crossing anything off the list that was over $150/night, unless it looked REALLY attractive).
Then we looked at how many rooms they had, and crossed off the ones that didn't have enough.
Then we looked at how many parking spaces they had (which for some was on their website, but some, we actually fired up Google Maps and counted spaces), and crossed off the ones that didn't have enough, or had significantly more rooms than parking (because, remember, Labor Day weekend, if we can't get the whole facility, there has to be enough parking for us AND whoever else is using it).
Keep in mind that we also need some space (not necessarily parking lot space, but if there's no other area...) for the vendors outside, and if one were to go for the BBQ in a tent thing, you'd need space for that, too - so layout's important as well. (A lot of resorts actually DON'T work well for this - and more conventional hotels can work far better - but some larger resorts can work really well. In the Denver area, when I was doing the initial research on it, most of the resorts were way too small, actually.)
One nice thing about resort amenities is that they can attract people to the event that want to bring their whole family - partners and children that are uninterested in TDIs can have something to do.
Also, there's the matter of how the hotel pricing works. I'll let those who are more intimately familiar with how that works discuss that in detail, but essentially, most hotels are making their money on the food (and a minimum amount of food purchased by the event is rolled into the room rate). That's why the at-hotel meals are so expensive. And, almost all of the weekend is about meeting people, learning about these cars, and having fun.
Regarding wifi, yes, this isn't a computer convention, but quite a few things are dependent on it being available, good, and free (and I've been to an actual computer convention where wifi in the rooms wasn't free, and the convention managed to get one DSL line serving the ballrooms - let's just say the ballroom wifi was basically unusable, and the cell carriers whose signal DID make it into the building, their towers went down under the load). Quite a few administrative workflows work much better when there's easy access to the internet - especially on-site registration (because the same online system used to preregister can then be used for on-site registration) and anything requiring payment. Vendors can use the wifi for their own payment processing if they're using Square or similar services, and some vendors that offer tuning require internet access to get their tunes. And, given that this is a community around an
internet forum, well, some of us just like to have the bandwidth taps flowing.
As far as the banquet being a formal affair, there are other meals that are informal (yes, ones held at the hotel are expensive, that's just how things go to get the room rates low enough) - the meet and greet, 2011's pig roast (which was AWESOME, and I'd love to see something like that again), and 2012's Kart-2-Kart pizza being great examples - and most of the event is meeting people, learning about TDIs, and having fun. Yes, there's a formal banquet at the end, but it's not all THAT formal (some people take it Very Seriously(tm), yes, but you won't get kicked out for not dressing up), and the auction is a major fundraiser for TDIClub.
That said, more affordable hotels are a good idea, as long as the facility doesn't detract from the event - but, on an inflationary basis, it's been getting
cheaper to stay at the host hotel. (No idea what meal prices have done, though.) And, a couple of the resorts vaguely near Chattanooga that we were looking at (plus a state-run "resort", which was rather institutional-looking (but would have been VERY cheap - like, list price $79/night for a hotel room), and turned out to not have enough parking) actually had multiple options - conventional hotel rooms with wifi and all, shared cabins, and camping, to cover several different price points.