I think it has to do with the manufacturers not understanding the spirit of the law in the US, that is, we can do anything we want until there is a law that states otherwise. Instead, they think we can't do anything until there is a law that says we can.
The FCC regulations on GMRS do not forbid having multiple channels of the same simplex frequency with a different tone, or no tone on each one. Same with repeater frequency pairs. They give us lots of channels but lock down those channels in ways that are not necessary, and like @amaff said, very annoying.