The only reason they are range limited even within the power restriction is an additional antenna restriction ??
Interesting reading here....
A friend of my dads when I was growing up was kind of into CB radios but in more of a ham radio way than "10-4 good buddy" way. He had crystals for his CB that supposedly gave him "private" channels. Not sure if that was uppers and lowers or the in between idea they talk about in the link above. Radios back then used a plug in crystal for each channel. Scanners did too.