What everybody seems to be missing that worries regulators/spectrum enforcers is that this opens the way for the radio equivalent of script kiddies.
Sure, you could disassemble your Radio Shack scanner, desolder this, resolder that, jumper the other, and receive whatever you wanted.
Now, you download this, dbl click that, agree to a EULA, and you're done. Better yet, a fairly simple data wipe of that directory, and there's no evidence.
Consider if this hack did apply to a transmit capable device:
Would you be comfortable with script kiddies being able to transmit on your local fire dept/ambulance freqs?
Do you really think a script kiddie will respect freq allocations? Even emergency ones?
Now, consider trying to track down every l33t teen kid who runs the software. Make enforcement a nightmare when you go from a couple of thousand complaints a year to tens of thousands a month.