NFL fining Terrell Owens is ridiculous

The NFL fined TO $10,000 for using a personalized prop, a little towel he used to wave at the Philly fans. This was done on the sideline and not in the end zone.
I believe T.O. waved the towel at the fans because they have been boo-ing him the entire game not to celebrate his touchdown, unlike his sharpie celebration a few seasons ago. The rule of the NFL is that no props can be used anywhere on the field so yes, they are right for fining but I wonder if he would have been fined if it wasn’t for the fact that it was caught on camera.
Larry Johnson celebrated his touchdown by grabbing a huge flag and sticking it in the end-zone, yet he wasn’t fined by the NFL. Sounds like a double standard to me.