Sounds unlikely to me. How would they detect folk who watch TV via ethernet? If they really did deploy wifi detector vans wouldn't folk just buy a bit of extra cat 5e?
I'll also warn my friend in Keffalania. He uses my VPN server to watch BBC iplayer.
Generally I agree with the license system because it frees our main public service broadcaster from making solely commercial decisions when choosing what programmes to develop. Subscription-based channels would be the death knell of quality broadcasting and imaginative decision-making.
It would make sense for BBC iplayer to be a subscription service, after all it is essentially a catch-up service. That way expats etc could buy in, without affecting the over all quality of TV and Radio service.