Speaking for myself, it depends upon the underlying reason (if it can be determined). In the case of, for example, the Advocate, it is obvious what their reasoning is. Many do it without malice.
Mine is the very same attitude I have seen expressed about "UAB" and "UCF". Those are the popular names their fans have chosen and prefer. I feel exactly the same way about "UL".
True fans are the ones who buy tickets, attend games, make donations, wear the colors and so on.