Wireless carriers have to unlock your paid off phone

[SickBeast]

It only costs $2 to unlock most phones anyways. The more serious issue is how they cripple phones by restricting them to certain frequency bands.

The only restrictions is LAC restrictions to keep customers on their respective carriers and in an emergency such as Katrina that is dropped.

Frequency bands are part of the Hardware.

For example I got my Galaxy too soon. I wanted 700MHZ but the revision I got does not have it yet. The newer Rev got a new nickname. The phone is the same except the 700MHZ is in it. There was nothing about this on purpose, it was just timing.

You can unlock frequencies by hacking your phone if you have a Qualcomm cpu. People have done it successfully. YMMV. Check on XDA.