[matthewmcg]

The requirement that scanners not be a silly modifiable to restore the AMPS bands was loosely interpreted. On certain older RadioShack scanners, you could unsolder some diodes on the main logic board and full coverage would be restored.

[NovemberWhiskey]

This is often the case for amateur radio equipment as well - transceivers are configured not to transmit outside the licensed amateur bands, but there is often a simple modification (cut a PCB trace, remove a component, etc) that happens to remove those limitations.

These are often called "MARS mods", since the Military Auxiliary Radio System uses HF frequencies that are outside the amateur allocation.