Your heart's in the right place, and I understand your frustration, but as a receiver of gpl software you don't have much of a standing. The company you speak of is infringing copyright by not distributing the source code with the binaries. Since you are not the copyright holder there isn't much you can do. You need to notify the copyright holder and hope they take action. Being pesty may get them to comply, but it's more likely it will take litigation to convince a company to look into their legal standing in the matter. If the copyright holder doesn't have the resources to fight the infringement, urge them to sign copyright over to the free software foundation.

As always, the fsf has said this better....
http://www.fsf.org/licensing/licenses/why-assign.html

In downtown Lowell that is exactly what they do. The meter people walk around with a wireless tablet that tells them which spots have been paid for, and prints a ticket for overdue spots. The system works fairly well until someone leans on the signpost and bends the number plate. If that person is nice enough to try to straighten the plate back out, the weakened metal breaks in some sort of accidental Luke Jackson act of defiance. Then a parking official comes by and puts a "No Parking, Out of order" sign on the pole. Can't park here son, no way to tell which two spots come between 155 and 158.