I simply disagree. There are programs with a much longer history of national prominence and much more significant national media presence who do not take steps such as an outright ban on signs. And I also know a number of alumni, young AND old, who value the atmosphere that is in part created by the signs and cheers and would be alienated by a move to eliminate them. If I was a big booster, I'd want to see a full, passionate, involved student section in every game because it is something that the rest of the fans value and something that the members of the team themselves enjoy. How many recruits have been quoted as saying that one reason they chose Miami was the devoted student fan base? How many current players have said in interviews that they love the students lined up hours ahead of the games? Moves like eliminating signs won't instantly destroy that atmosphere, but I would argue that over time it does chip away from it, draining the energy from the core of the student fans.
I'm not saying they shouldn't try to eliminate vulgarities. There are two ways to do this: unilateral, outright bans or engaging the student fans toward cooperation in solving the problem. The former approach will alienate students and most likely fail as far as eliminating the vulgar cheers... the only way you would actually achieve this is through ejections and individual bans, which hurts student morale and game atmosphere even further. The latter approach gives the students a sense of involvement, investment, empowerment that will provide a strong motivation to self-police. Then you get signs and chants that are fun, witty, and contribute to the atmosphere, AND you maintain a robust student section. If at that point students fail to self-police, they then have no legitimate complaint when a ban has to be imposed instead.
Of course this is all premised on the assumption that signs are in fact banned. If that turns out to indeed be the case on Friday, we can explore this further. As I said, though, you don't have to hire more people to monitor signs... those people are already there regulating the gate and have already been doing this additional job. As far as a concern that we need to avoid offending big boosters, I would argue that today's most diehard student fans are tomorrow's biggest non-player boosters... discounting and alienating them hurts in the long run. As far as families go, it's an athletic event with invested fans. In my experience, you hear worse things in worse contexts at most other venues with similarly impassioned fans.