In my country (Italy) we kept receiving threatening letters as well as random phone calls, sometimes even attempted inspections although unless they came with the police and a warrant you simply wouldn't let them in. Some context: the original law declared the tax was due for state owned TV reception, so when in the late 70s to 80s private owned TV stations boomed, some people modified their TV sets so that the state TV could not be received. Problem solved? Nope! the government promptly modified the tax into a more general tax. The text is so vague that it could be applied to cellphones and computers too, although they always told that's not the case, but the vague text remains. Anyways, letters, phonecalls and random visits went on for decades, then a few years back a genius politician solved the problem by integrating the TV tax within the electricity bill. If you don't own a TV set (and know your rights) you can still declare that and get the amount cut from the bill, but that will ensure an inspection will follow.

Thanks. In Greece also (where I'm originally from) the TV tax is rolled in to the electricity bill and you can opt out. I haven't heard of any inspections but that's because nothing works in the Greek public sector. Or anywhere in the whole country.