I can't believe this subject has garnered three pages of conversation.
Those that have told us to call them "orange" instead of "red", or "purple" instead of "blue", are probably not going to care either way. But regardless of the possible repercussions, why not just call the team wearing orange "orange"?
Besides, in our pre-game meeting with each team's captain(s) we let them know what color they will be called. If they want to be called something else due to school pride regarding their colors... who cares? Just do it.
BTW, it looks like orange and purple are there now.