They're also benefiting from being practically the last man standing in the family dining segment. They're not in a menu category that was going to butt up against nicer sit-down dining places (if Olive Garden, for example, raised their prices much they'd be running up against sit down Italian places, likewise for Red Lobster and nicer seafood). And they adapted well to the COVID-era takeout boom, which suggests that they were actually serving food people would choose to eat, not merely offering the sit down experience like say Applebees.

All the expensive local run city restaurants benefited from inflation.

The McDonalds burger went from $12 to $18, but it's still the same terrible product. The hipster burger joint price went from $20 to $22, and that is a dramatically better burger.

The difference is that the local burger place doesn't have to show a 7% increase in profit year after year in perpetuity. Their price was set for "I can live a modest life off the profit and pay my employees a wage competitive enough to actually staff my restaurant, and therefore also end up with people more competent than your average fast food worker". That gives you more value per dollar, because more of your dollar is being spent on actual product and service rather than paying absurd and unjustifiable salaries to an entire building full of overpaid "management" and administration in the highest cost of living part of the country. Fewer shareholders to pay too.

So instead of the price delta between absolute trash and quality being $8, now it's $4.

I am told inflation is a bad thing, but it is making lots of small business that we desperately want and need much more competitive. A smaller business has far less pricing power and therefore less ability to pass on a cost increase.