Only a handful of small specialist firms actually just move bits in the UK. Every single UK ISP big enough to advertise on television is signed up to filter traffic and block things for being "illegal" or maybe if Hollywood doesn't like them, or if they have "naughty" words mentioned, or just because somebody slipped. If you're thinking "Not mine" and it runs TV adverts then, oops, nope, you're wrong about that and have had your Internet censored without realising it. I wonder how ISPs got their bad reputation...