And there is nothing even uniform for each particular casinos.

Some give different amounts for the exact same coin in to females over males for example. Some give more to people with Asian names. Some give more to out of town than locals. Some give different amounts to different certain zip codes, based on average incomes.

And some will give different amount to the exact same player for the exact same coin-in. It is very common for a casino to drop the amount for the same coin in and see if they can get you to come back for a lesser amount.

Some of these "targeted" offers should probably be illegal, but either way, you are demonstrating FAR beyond any doubt that YOU know nothing about the subject matter.