Want to keep restaurant prices down? Stop stealing.

Everything affects the price you pay in a restaurant. We have talked about the rising cost of food, and the price of liquor is continuing to climb. Beer prices are up in general, and craft beers are skyrocketing. Coffee has gone up more than 20% since the beginning of the year.

Theft drives prices up as well — and I’m talking about guests, not staff. After a guest thief takes what they want, guess what? The restaurant must purchase replacements and eventually report the thefts to their insurance company, which in the long run will raise their premiums.

Here’s how some guests justify stealing.

‘I just spent a lot of money’

A guest at one of our nightclubs, who spent $5,000 to get $5,000 worth of food and beverage to entertain his 10 guests, took the $500 glass centerpiece on his way out. When we called him the next day, he justified his theft by saying, “I spent $5,000, so I decided to take the centerpiece.”

Well, I recently spent $3,000 at Best Buy for several household appliances. When I paid the bill, I did not go back to take a $500 item for free because I spent so much on my other items.

We let our thief know that we did not agree and that he should bring back the centerpiece. He resisted — until we told him that his theft was on camera and that we would be putting it on Facebook along with his name.

We had our centerpiece back the same day.

‘These plates will look great in my home’

One of our fine dining restaurants whose check average is well over $100 per guest continues to have a big theft issue. The restaurant has show plates that are on the table when the guest arrives, and each plate costs $100.

A few months ago, a guest put two of the plates in her purse. The server did not know what to do and did not want to confront or embarrass the guest. I had the manager put a $400 charge on the check for “gift plates.” The guest pulled the plates out of her purse immediately.

‘I collect autographs’

There are great sports bars and steak houses that go out of their way to put up rare, autographed photographs and memorabilia from athletes and celebrities in their establishments. Next time you go to one of these restaurants, look closely at how the items are mounted on the wall. Most often they are screwed in tightly or behind a security glass. This is to thwart guest thieves who were taking them off the wall and taking them home as collectors’ items or to put on eBay. These are one-of-a-kind items with real value, but somehow guests feel justified taking this property.

What’s mine is mine — and what’s yours is mine?

We went to dinner at a fun Italian restaurant and loved their espresso cups. We asked if they sold them and they said they did not. The manager came out and told us he had some that were slightly chipped, and would we like to purchase a set of four. We said yes and now we have four unique espresso cups, bought and paid for, no thievery required.

Here is a great idea. If you like the show plate on a table, take a picture of the bottom so you can find them online when you get home. Or at least ask the server if they’re for sale.

Restaurants already are operating on very thin margins. Don’t make it harder for them.

• Izzy Kharasch is president of Hospitality Works and has worked with more than 700 restaurants around the country. He offers restaurant, bar or hotel owners a free consultation. Email him at Izzy@hospitalityworks.com.