Yeah, it takes a bit of getting used to. In the places I'd lived previously you'd often not even arrive at the pub until 11. But one of the amazing things about the UK is the number of pubs there are. They are everywhere, even in the country and the suburbs. It's unusual to not have at least a couple of pubs within easy walking distance of your home, wherever you live. Because of this, licensing laws aim to limit late night noise. Hence no booze sold after 11.
Pubs can apply for a late license but because they're expensive It's usually just night clubs that get them. I think if NFL games were on Saturday more pubs might try to get a late license but the lack of randoms out getting boozed on sunday means it's not worth it for them financially. Sports bars are often allowed 5 per year which they use for the Superbowl and rugby matches in NZ or Australia which would get the biggest crowds.
That said, there may be sports bars with a late license that I don't know about.