Is it really necessary anymore to sing national anthems at sports events?

They are after all, just games. I see a national anthem really has very little to do with two teams, in the case of NHL or NFL, who really are trying to maim, to at least a certain extent, players on another squad. Also, and this may not be popular, I see little point in singing the national anthems at Olympics, which are more about what country is “better” because they churn out more gold medals than some other country.