Who is being unreasonable?
Short answer: everyone. FGS, where are people's manners these days, especially when it comes to weddings?
I'm not a football fanatic, even though I understand that some people are. And I wouldn't be inclined to leave a wedding to watch a game; that's just rude. You can easily keep up with the scores with an odd glance at online updates, and watch the game later.
But as for the message put out by this precious B&G, words (almost) fail me! Nice little prince and princess, aren't they? For fun, let's dissect their message piecemeal:
they have chosen not to screen the champions league
Fair enough.
and they do not want anyone to ask for it to be put on
OK. Again fair play.
to leave and watch it
Yes, I do agree this would be rude. But in the end, provided there is not a mass exodus leaving a half-empty room behind it, I can't see why this should really encroach into their day. They are hosting an event, not forcing attendance at an unwelcome team-building activity.
or to be watching it on any devices
Get stuffed. People can watch exactly what they like on their own devices. This is not for you to dictate. Who, exactly, do you think you are?
and to please respect that this day is about them.
Fuck off. And while you're at it, kindly stuff your invitation into a dark orifice.
Where on earth does the world find these precocious berks?