Do you need to have proof of age when entering, like a passport?

No, we have been there many times... Nobody asked us until now..

Never been asked

No

I don't recall been asked for I.D because the time I went I only went with the purpose of going bowling. I do believe that if going to seat bar or ask for an alcoholic beverages they will check if you are old enough.

Not unless you are in a club.

Bring your green card

A passport will work, but they need to check your age to know if they should give you an underage or above 21 bracelet

Yes