That's like me claiming the BYU fans I see doing the "Y" hand sign haven't ripped off the "hang loose" sign. If in a couple of years the entire fanbase starts doing it, how would I know the individual or individuals that made it really popular didn't get it from surfers? And if that person or group of people didn't, does that make it any less of a rip-off of "hang loose"?
The fact of the matter is that the "U" is an iconic Miami symbol and Utah now uses it on a wide scale, when they didn't previously.