9th Annual "Paws for Style"

Lauren Conrad might spend her life around some really big bitches, but lil' ones just won't do.

Sources tell TMZ that LC got $20,000 -- yeah, we know -- to make an appearance and walk the runway at Animal Fair mag's "Paws for Style" event last night in NYC. She did the whole red carpet thing.

But, when it came time to do the runway, our spies say she threw "a hissy fit" and "stormed off" in tears, refusing to prance down the catwalk with a dog. We're told LC claims she didn't know anything about the walkin' the dog.

Her rep couldn't be reached immediately for comment.

source: tmz.com