how old is too old for a Chuck E party?

C had a few parties at the Chuckster's back in the day and of course we made it to an email list at some point so we get special offers & coupons from time to time, almost always around the birthday wanting us to book a party. C is going to be 10 this year and his last party with the big rat was 5 years ago so my question is when is it exactly they stop offering to book a party for him....when he is 30?