The reality is that casinos are profitable operations, like any other business. When their very sophisticated forecasting models show elastic demand for rooms/gambling, they'll add perks or throw in extras to bring more peeps in. When their models show inelastic demand - that is, about the same demand among a range of pricing schemas - they will push towards the highest rates the market will bear.
In the 60s, 70s, 80s, and even 90s, such very sophisticated forecasting and revenue management models simply didn't exist. So you had a lot of anecdotal "free stuff" thrown about. Once it was proven that such perks didn't actually work (and no, one geezer standing up and saying "It worked for ME!!!!!" doesn't count), you began to see free stuff restricted and extra revenue add-ons like resort fees, wifi charges, etc.
Virtually the entire audience for Strip casinos these days is travelers. A growing percentage of pre-COVID revenue was coming not from shows (many in decline), but day clubs at pools. Target: 20-somethings with lots of cash and very little in the brain department. Most of the Strip casinos couldn't give a flying turd about locals. And why not? In 2020, there are outstanding local off-Strip casinos that can do that job for them - Green Valley Ranch, Red Rock, the M, and so on.