This really bothers me. I don't care if someone is "cheery" as long as they just do their job. People justify tipping service personnel (bar tenders, waitstaff) over them getting a fair salary because if they didn't tip "how would I get good service? There's no incentive without a tip." I believe some people believe "good service" means fakely cheery while to me it is "you brought me my food." If you aren't faking a smile and elevating your voice you are being "rude."