Canadian BETS Rules

That's easy, we don't and we can't. Broadcasters can't use those "crappy" antennas, nor would we want too.
Have you ever seen a REAL FM array? Typically there are several antennas lined up that we call a "Bay" that adds gain and reduces picket-fencing as well as other issues. What if I told you an FM exciter is seldom set to the "licensed" power and is usually either much higher or lower in power depending on the antenna gain. For Example, our FM translator spits out 782 Watts and is licensed for 250 watts and our Class C FM transmitter pumps out 27.5kW on a 50kW license.

When it comes down to it, all FCC licenses are based on field strength and protected contours, same as Part 15 with the exception of .219

In Canada and the U.S., as far as I've been able to determine, the only users of 76-88 are TV stations, and licensed wireless microphones. The entire whitespace device initiative being undertaken by both countries is to allow unlicensed devices, such as low power wireless microphones, internet routers, etc., to use the space vacated by TV stations without causing interference to the remaining current licensed users (that's where the geolocation checking, license database, etc. comes in.

In the U.S., the big question is whether unlicensed broadcast transmitters can be considered whitespace devices - they would have to meet all the technical criteria, of course. Given that such a transmitter is virtually identical to a wireless microphone transmitter (potentially minus the microphone), I can't see why not, but you never know. The FCC has excluded specific uses for certain frequencies before this.

In Canada, 76-88 Mhz is to be used for non-broadcasting services (where broadcasting is defined as transmitting to the general public). But just as RSS123 is considered non-broadcasting (because your audience is to those within a confined boundary, such as a mall, or private property), I don't see why something like RSS123 couldn't be done in those frequencies - again, the transmitters would have to meet the whitespace device technical criteria. However, given Canada's predilection for making the simple complicated, I wouldn't be surprised if RSS123 was excluded.

Posted the USA and Canadian RF allocations in a new post.

From what I can see in those charts, the only official users of 76-88 Mhz in the U.S. are broadcasting and maritime, in Canada broadcasting. Considering that a lot, if not most, of the broadcasting is gone or going, those frequencies are going to be open in most areas (if there is maritime use, it will obviously be only near waterways). That's the reason for the whitespace device initiative.

In my opinion, the thing to do is to get confirmation in the U.S. that whitespace broadcast transmitters would be equivalent to whitespace wireless microphones - and they are (in my opinion), for all intents and purposes. Once that has been accomplished, then unlicensed broadcasting with up to 1 watt would be good to go in those frequencies (assuming, of course, that someone is willing to manufacture said devices, or a wireless microphone with an alternative input such as an RCA or 3/8 inch plug).

I doubt very much that hobbyist broadcasters would have the clout to get dedicated frequencies, but this would still be pretty good. In rural areas, where there are few if any licensed whitespace users, hobbyist broadcasters could probably use that 1 watt that has been talked about.

Potential listeners will still have to get radios that can receive your station.  Perhaps sell them at cost?  Or give some away as promos?  It could also be an interesting business venture for a small business in a rural area served by a hobbyist/community station.  As has been pointed out, some radios do receive 87.7 and 87.9, and under the whitespace rules those frequencies would be valid for hobbyist broadcasting if there were no licensed users nearby.