I actually don't think it has anything to do with that tenet. It's simply a basic principle of fairness: if you're going to allow Christian clubs, you should allow Satanic ones, too. TST doesn't attempt to set up After School Satan Clubs in schools that don't have a Christian club, which goes to show that it isn't about offense but equal rights.

Moreover, TST doesn't try to force other people to obey their tenets. One of the things that Satanists hate about Christianity is that they try to force people who are not in their religion to obey the rules of their religion. Satanism doesn't (and shouldn't) do the same thing.