I hate that, Adelaide! One of my brothers-in-law used to be like that (he's become much more friendly since, thank goodness). When he and my husband's sister were newly married, they joined us for a Christmas Day family gathering at our house. BIL went downstairs to our rec room and turned on The Game rather than socialize with the family. I was royally ticked (I was brought up to NEVER turn on someone else's TV without permission), and when the entire family adjourned to the rec room after dinner, I turned off the TV and said "Sorry, BIL, but the TV stays off while we're visiting." He stomped upstairs like a kid having a tantrum (he was in his 30's at the time), muttering angrily "I can't even watch The Game!" SIL then turned to her brother (my husband) and said beseechingly "Can't you let Tom watch The Game? Don't you want your guests to be comfortable?" My husband said reasonably "But Lori, we don't like sports. If we turn on The Game, we won't be comfortable, because we won't be able to have a conversation. Don't we matter, too?" She didn't have an answer for that one, and she and BIL left shortly afterwards.
Ever since then, when we've visited their house, The Game has been on in the livingroom. And yes, we find it impossible to have a conversation. I've had to bite my tongue to keep from saying "There's a Doctor Who marathon that I'm dying to see. Can we change the channel? What do you mean, 'no'? Don't you want your guests to be COMFORTABLE?"