It seems that these Belkin beasts use the Gigle mediaxtreme chips. These don't just cover the HF spectrum, they transmit at up to 300MHz.

Now, external noise reduces with increasing frequency, and these things will have to inject even higher levels of signal because mains wiring is so much more lossy at these frequencies (it's meant for 50Hz you see). Since receivers at VHF frequencies are so much more sensitive because of the increasing RF path loss with frequency, it means the potential for interference will be much greater.

Just maybe if the interference generated is enough to wreck people's Band II FM reception then this menace will become so widespread that the EMC regulators will have to take action and force the manufacturers to make them EMC compliant or take them off the market.

We can but hope that some degree of belief in the rule of law returns.