Especially when they never tried it before.
In a battleground appearance dosen't mean anything, People don't look at your character, they are busy fighting. The enemy team barely se your gear, most only se a red bar, if your so obsessed with your gear that you can't take your eyes of it to spot enemies then... well.... you don't belong in a BG.
I love the transmog system and I'm myself obsessed about "looking good" but in battlegrounds? seriously? no, it feels like most of the people hang on the band wagon and just TRY to find something of a valid reason to complain about this feature, and to be honest, it's bad.
I guess some very few people do care about this still, ok then why not have option to set what race of the other faction you want to look like?