Anyone who has worked in the restaurant business will be happy to tell you that waiters always fight each other to avoid working Sunday lunch shift. Not because they want to sleep in, but because it’s a widespread belief that the post-church crowd is loud, demanding and unwilling to tip appropriately. In the food service industry, “Christian” is synonymous with “selfish.”
Source: Here’s how the philosophers of selfishness came to use Christianity as their cover story | Alternet