It's mostly all smoke & mirrors. The basic rules of FPV flight exclude the need for any additional boost of signal strength.
I don't know about the rest of you guys, but my P4 will easily fly so far away with full control that I wouldn't be able to find it with an excellent pair of binoculars. As far as that goes, I'd much rather risk irritating the FCC than the FAA. I think the relative investigatory and enforcement authority of the FCC is pretty tame compared to what the FAA can do. Both agencies are rather tame, however, compared to the FBI & the US Postal inspectors.
I had a felon working for me many years back that had been charged with breaking into USPS stations and stealing large volumes of stamps. He told me that the postal inspectors were ruthless in their pursuit of him. Canada wouldn't extradite him, so the postal inspectors ended up kidnapping him illegally out of Vancouver so that they could arrest him on the ferry boat within the USA borders. But that tale isn't related to any drones, so it's a bit off topic. Nonetheless, it does demonstrate that federal agencies sometimes do what they want to do, regardless of the rules.