Who keeps saying those things?

|A man walked in to a bar after a long day at work. As he began to drink his beer, he heard a voice say seductively "You've got great hair!" The man looked around but couldn't see where the voice was coming from, so he went back to his beer.A minute later, he heard the same soft voice say "You're a handsome man!" The man looked around, but still couldn't see where the voice was coming from.When he went back to his beer, the voice said again "What a stud you are!" The man was so baffled by this that he asked the bartender what was going on.The bartender said "Oh, it's the nuts--they're complimentary."