It's bad for Tracfone when they do this, but it's not illegal and the only way it could have anything to do with terrorism is if they use the profit to fund it.
Or used them as detonators...
Using a cell phone as a detonator is a real bad idea. They've run out of cell phone numbers and are recycling them. I get two or three calls for the previous owner of my number a month, and I've had it for two years.
You wouldn't want to get a wrong number while you were arming a bomb with a cell phone.