Because no one lives in isolation, we live in society and people like.....talk to other people.
Like I said, the opinions of others might not matter to you, but it might matter to those who are in a relationship with you (like Pink for example) and it might bother her.
I am not saying that everyone does, I did not ever write that. Everyone is individual and I find it is more often those who ARE married, who say it doesn't matter....
Yeah not to you it doesn't...what about her?