(benign) peak-to-average problem - I'll go ahead and just assume that defcon attendees use a lot more internet bandwidth than the average Vegas-goer, so during defcon the network is overwhelmed, but the rest of the year the capacity is adequate. Upgrading the links to satisfy the peak (defcon) traffic load costs the casinos significant money, but gives minuscule benefit since the rest of the year they only need to support the much lower average load.
(malign) the casinos don't actually want you to have good internet because they don't want you staying in your room internetting - they want you down on the floor gambling. Other non-gambling amenities (shows, restaurants, etc.) are mostly time limited - you only spend so much time eating, and shows are only a couple hours each - and can be a differentiator that draws people to a specific casino (because of specific food/entertainment preferences). Those people then spend the rest of the day gambling at that casino.
"Better" internet it's actually a negative differentiator - people who want to spend all their time infinite-scrolling will gamble less, so casinos don't want to attract them in the first place.
Event venues AND anyplace that might EVER have expense account holding business travelers just want to charge for it. Even if fiber literally rolled right up to the side of the building, it'd be resold by either the hotel or a 3rd party vendor with a focus on profit rather than just being good.
My wife and I started traveling a lot as leisure travelers (50+ days last year, 240 days the year before) post Covid and my wife goes to conferences. We stay in mostly Hilton and Hyatt brands with the occasional Marriot. It use to be true that the high end brands charge for WiFi. But I haven’t seen a separate WiFi charge in all of these time.
Admittedly the only hotel I stayed in that was considered high end was the Conrad in Los Angeles.
Non anecdotally, I did a search and I couldn’t find a hotel that still charged separately for WiFi, just a “resort fee” that everyone pays.
(benign) peak-to-average problem - I'll go ahead and just assume that defcon attendees use a lot more internet bandwidth than the average Vegas-goer, so during defcon the network is overwhelmed, but the rest of the year the capacity is adequate. Upgrading the links to satisfy the peak (defcon) traffic load costs the casinos significant money, but gives minuscule benefit since the rest of the year they only need to support the much lower average load.
(malign) the casinos don't actually want you to have good internet because they don't want you staying in your room internetting - they want you down on the floor gambling. Other non-gambling amenities (shows, restaurants, etc.) are mostly time limited - you only spend so much time eating, and shows are only a couple hours each - and can be a differentiator that draws people to a specific casino (because of specific food/entertainment preferences). Those people then spend the rest of the day gambling at that casino.
"Better" internet it's actually a negative differentiator - people who want to spend all their time infinite-scrolling will gamble less, so casinos don't want to attract them in the first place.