Pay-As-You-Go Phones in Airports

I forgot my cell phone at home on my recent flight from Seattle to San Jose. I realized this at the Seattle airport after it was too late to go home and get it. No big deal, I thought. I’ll just pick up one of those pay-as-you-go phones in the airport while I wait for my departure time.
Wrong. According to people working in an airport shop in Seattle, it’s against the law to cell these phones in the airport. I haven’t been able to verify this, but since they sell numerous cell phone accessories, I’ll assume the clerks know what they are talking about. The implied reason was that the phones could be used for terrorist activities (presumably because you can pay cash to get one).
I might buy into this theory if it weren’t for the fact that thousands (maybe millions?) of cell phones pass through airport security on any given day. All the phones that go through security are deemed “safe”. Am I to believe that none of those phones are pay-as-you-go phones? Not likely. If we operated on the same logic used for not allowing liquids to pass beyond a security checkpoint, I should be throwing away my phone before checking in and buying a new phone on the other side. I certainly would think it is harder to misjudge a complicated electronic device like a phone before you’d mistake a bottle of water someone sips from.
When I touched down in San Jose, my first stop was a nearby Target store where I picked up the Virgin Mobile Kyocera Switch Back. I don’t think I’m ready to dump my Windows Mobile phone just yet, but I could certainly use this phone instead of many other alternatives from Cingular. The keyboard is functional, the camera takes decent pictures, and the audio quality is as good as anything else I’ve used. It even worked as my alarm clock. If the airport had carried this phone, they could have had my money instead (and required a credit card to prevent anonymity).