Politicians, snakes, rats, spiders, salespeople.
In that order, these are the things people despise the most. I bet you can guess why salespeople made the list. When I ask my clients in training to name the characteristics and attributes of 'sales people', they respond with the following objectives: pushy, manipulative, cheesy, out for themselves, liars, cheats. Mind you, this is coming from people who SELL for a living!