It used to be that if one mobile carrier raised activation fees, rival carriers wouldn’t publicly slam them in part because they wanted to reserve the right to raise fees of their own. However, T-Mobile CEO John Legere has taken a different tack, which involves trolling ATT nonstop for just about everything it does. So when news broke Wednesday that ATT would be raising up its smartphone activation fees for customers who buy phones on contract, Legere predictably pounced and use it as yet another club with which to beat Ma Bell. “Is this a joke, ATT?!” Legere wrote on Twitter. “[T-Mobile] removes fees and you do the opposite!? What happened to copying us?” Of course, in ATT’s defense you don’t