There’s a conventional wisdom urging customers to be kind to service staff. While it can be frustrating when orders are taken incorrectly or when food or service is slow or unpalatable, mistreating those who are providing direct assistance can have its consequences. After all, there’s no telling what one might do to food or how those serving you might turn anger and frustration around to impact your overall experience.

Restaurants are the most obvious locations where one should probably watch his or her tone. But “Good Morning America” points out another potential bastion to beware of: hotels and motels. In an interview with Jacob Tomsky, who has extensive experience working in the accommodations industry, some of the dirty details of how hotel staff can make one’s stay miserable were recently provided.

Tomsky, who penned a new book, ”Heads in Beds: A Reckless Memoir of Hotels, Hustles and So-Called Hospitality,” exposed five of the tactics that staffers often use to get revenge on rude and angry customers.

5 Secret Ways That Hotel Staff Get Back at Bad Tippers & Nasty Customers

The Plaza hotel in New York City (Photo Credit: AP)

First, there’s the valet — the first person that guests encounter. According to Tomsky, it’s important to give this individual a tip, as there’s no telling what he or she will do with your vehicle if you don’t. In fact, he said it’s not uncommon for valets to take your car for a joyride after you hand the keys off, specifically if there is no tip given or mistreatment.

“A valet parker probably got hired last week, probably getting fired next week, doesn’t really care that much,” he told GMA. “The valet is not going to make any money unless he gets that dollar tip.”

All rooms aren’t the same, he contends. So, a tip at the front desk might also be beneficial. On the flip side, acting nasty or even speaking in a negative tone to those traveling with you can have dire consequences. Since some rooms are poorer than others, the associate helping you may stick you in a sub-par room without even batting an eyelid (and without you knowing what you’re missing).

And, as GMA notes, hotel visitors in New York City might want to avoid room 1212 (another place where angry hotel staff could end up placing unruly customers):

It may sound like a good deal — a high floor room can come with beautiful views — but Tomsky said it’s not.

He said some hotel guests don’t know that when using the room phone, you have to dial out first, typically by pressing an 8 or a 9, to place a call outside of the hotel — and 212 is a New York area code.

“If I put you in Room 1212, it’s a beautiful room by all accounts,” Tomsky said. “However, there are a bunch of idiots all through the hotel that don’t dial out, and they’ll type 1-212, they’ll start typing any local number and it’s going to ring 1212 all day, all night.”

The tips, too, carry over to the bellman. Tomsky recommends that guests allow these workers to carry their bags rather than transporting one’s own luggage in an effort to avoid paying them a tip.

“The bellman and the doorman are very good at lingering, it’s a very strong skill,” he explained. “If they stand a little too long, making you a little too uncomfortable, and then you’ll reach for your wallet.”

And last but not least — treat the cleaning staff well. But even if you don’t have any run-ins with them, be sure to use either plastic cups or wash out the glass cups that are in the room. With limited resources, Tomsky claims that cleaning staff end up employing the use of the same supplies they use to spruce up surfaces to get the cups clean (i.e. rather than soap, they might use shampoo or Pledge).

Read more of Tomsky’s tips, particularly when it comes to waging an effective complaint and canceling reservations, here.

(H/T: ABC News/”Good Morning America”)