I think they have the right to refuse service to anyone.
Typically no one excludes customers, but on game day they will have no problem getting them.
As long as it doesn't target race, color, religion, or natural origin I think they are good as long as they have proper reason.
http://www.legalmatch.com/law-library/article/restaurants-right-to-refuse-service.html
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What Conditions Allow a Restaurant to Refuse Service?
There a number of legitimate reasons for a restaurant to refuse service, some of which include:
* Patrons who are unreasonably rowdy or causing trouble
* Patrons that may overfill capacity if let in
* Patrons who come in just before closing time or when the kitchen is closed
* Patrons accompanied by large groups of non-customers looking to sit in
* Patrons lacking adequate hygiene (e.g. excess dirt, extreme body odor, etc.)
In most cases, refusal of service is warranted where a customer’s presence in the restaurant detracts from the safety, welfare, and well-being of other patrons and the restaurant itself.