But I'll eat until they kick me out. That's how I know I got my moneys worth

I'm not sure what you mean. Most buffets won't limit you.

Buffets have inherent limits in the way they do things. It's just transparent to you unless you know what to look for.

Limited buffet hours. Most Indian buffets are lunchtime only, and the restaurant is open, say, 11am-1pm, and then closes until dinner. Indian buffets are often leftovers from last night's dinner, too, so there's a limit to the amount of food that they won't cook more.

Size of plates, bowls, glasses. This is an easy one, and you can use it to go on a diet. If you have large plates or bowls, throw them out and get small-capacity dishes. Buffets will make you use a certain size plate, and so each trip you can only pick up so much food, and this helps you notice that you feel full before taking more.

You may also be required to use a clean plate each time you dip into the buffet. This might have various effects on how you regard the food you took originally.

It's still fair to say unlimited for all of those except not cooking more. Much like you can easily have an unlimited 1gbps connection. (Or 'unmetered' is advertised sometimes.)

There is always a limit even if it's not published.

For what purpose? People can only eat so much. The buffet doesn't have to limit you. And if the buffet isn't limiting you then it's valid for them to say "unlimited".

I'm not sure what you mean, as far as buffet dark patterns go, nothing really unreasonable happens that comes anywhere near the limits of the human stomach.