News flash, Portland: Your restaurant servers don't always like you. And they've got their reasons.

As a public service, the Bite launched an old-fashioned gripefest. We wanted to find out what really ticks off local waiters and waitresses, from no-brainers, like bad tips, to "old-lady perfume." You don't have to take their professional table advice, but remember: According to the U.S. Department of Labor, there are more than 24,000 servers here in Oregon.

Tribulations start at the cafe door. "People will inevitably sit at a dirty table," says Colosso server Matt Dickel. "The entire restaurant will be empty, and they'll sit at that one table that hasn't been cleared yet. They assume somebody else sat there, so it must be the good table."

Over at the new Cuban hangout Malanga, on Northeast Fremont Street, servers believe that people who use cell phones while dining are akin to the devil--as are individuals who snap their fingers to get a waiter's attention. "We're not dogs," says Kate, who, like many of the servers we talked to, asked to be identified only by her first name.

We got an earful of gripes from Stephen Dingell at the Heathman Restaurant, where the dining room gets swamped on the nights when the Schnitz concert hall has a show. "We tend to get a senior crowd and, God bless them, they have very unrealistic expectations," Dingell says. For example, there's the octogenarian table that wants to cobble together its own wheat-, salt- and butter-free entrees from the menu and still make an 8 pm curtain call.

"No salt or butter? We have a master French chef," says Dingell, who's been a Heathman fixture for 19 years. "I've trained some of my regulars. It only takes five or six years before they trust me and just come early."

But it was the crew at Mother's Bistro that really let loose, explaining different types of bad diners. There are the "self-seaters," the "enablers" who stack their own dirty plates, as well as "table commandos," the micro-managers who order for their entire party.

"One word--decaf," says a longtime server at Mother's who offered his name as Doogie. "People always ask, 'Are you sure it's decaf?' This is how I pay my bills. Of course it's decaf. Stop asking me."

The bistro's grill cook, Robert, also joined the gripefest. He used to work as a waiter at an upscale Portland eatery, where he cleared more than $80,000 a year in tips and salary. But he took a pay cut when he left that job to become a cook, and his reason is simple: "I hate the public."

"There are a lot of customers that make life miserable," agrees chef-owner Lisa Schroeder. "Since I own a restaurant named Mother's, I feel like I'm obligated to teach people how to behave."

Schroeder lists such sins as diners who plop ice into a glass of red wine or who don't spread napkins in their laps, but her worst mom looks are directed at penny pinchers. "It makes me crazy when customers pull out the calculator in front of friends," the chef says. "Come on! Just split the bill! Oy."

Check, please.