and you've trained everyone

Training is a great, important word here. There's a huge lag between setting prices and having them affect your business. Most people will try a new place once, regardless of the price. The first time they go they'll judge the price by the style of restaurant. It's not until the second time they'll factor the price into their decision. Companies only care about "training" when it goes the other way, when it's a good reputation they can liquidate through enshittification.

When they're on the downside of training all they think about is "MONEY NOW" while they're effectively scamming their customers and slowly destroying their customer base.

There's a hot chicken place near me that's having exactly this problem. The downtown, novel location in the middle of the walking market (a tourist attraction) was a bit expensive, but good. They expanded out to the suburbs, kept the downtown prices, and no longer give sweet tea for free. And somehow they're surprised that less than a year after opening they're lucky to have three customers at once. I'll give you a hint. You're charging $10 for a chicken breast on a slice of wonder bread. Chicken used to be popular because it was cheap.

https://hotchickentakeover.com/menu/

Compare to this 2005 Popeye's commercial. 11 pieces of chicken for $10. Not a single breast. Look me in the eye and tell me prices have actually risen 11x in 20 years.