scottydl said:
Is this sarcasm? (I honestly cannot tell.)
I asked my question because it really doesn't seem like problems would result from limited public use of certain radio waves. I say "limited" since radio communication (by voice, i.e. Handheld or console radios) is fairly rare these days. I can't imagine any particular kind of chaos ensuing.
Perhaps you don't recall the early CB band, right after the FCC dropped licensing requirements (but not tech standards, such as max power out, etc.). Unrestricted use with more than a watt or so, and especially if it also allows more efficient (and even remote) antennas, can be a problem over more than a few hundred feet. Even today, CB can be chaotic, at times, though the long antennas required still don't give portability quite as easily as the FRS.
Lou pretty much has it right above, except that what Happy points out is a statement that, while it is often technically correct, certainly needed clarification, since many ham radios are CAPABLE of transmitting well beyond the ham bands, but there are many legal restrictions on hams as Happy points out, including the specific frequency ranges on which they are allowed to operate and what type of transmission is allowed (AM, FM, sideband, CW, digital, etc.) in any particular band segment, even how much power a license type and/or freq band allows.
Note, too, that amateur radio is a "radio service" that specifically allows experimentation on any of its allocated freqs (some of which are secondary allocations), and has very specific requirements about what may be transmitted (i.e. no music, no "commercial" traffic, restrictions on 3rd party operations, and much more).
But, as Lou so carefully points out, the big reason is to maintain some semblance of order and usability on the various spectrum segments.
And even FRS has specific rules that must be followed, though I suspect that few know much about that.
