Having been "adopted" by GrannyandGrandpa (HI!! Hope to see you in St. Louis for the game on 9/2!) and having attended numerous ISU games with them over the last 5 years, I think it's safe to say that you don't have to worry about offending their sensibilities, but you may need to worry about your own!!! I've seen Granny go on some referee and coach rants that would make some blush!
Barb