One good reason to pay your restaurant bill in cash: Tipped employees get that money right away without having to worry about being docked fees for card-processing. Another good reason: A scammy server can’t artificially inflate your credit card tip with some crafty work of the pen.

WTAE-TV reports that a waitress at an Italian restaurant in Pennsylvania was caught doctoring low-dollar credit card tips to enrich herself (and feed an alleged drug problem).

So if a customer wrote in a $5 tip, police say the waitress would write in a “1” or “2,” suddenly increasing that to a $15 or $25 tip.

Of course, if you’re leaving a $5 tip on your meal, that means you probably only spent around $20-25 on food to begin with, so customers are going to notice when they’re ultimately charged upwards of twice the menu price.

And they did notice, complaining to the restaurant about the apparent errors.

“We figured out who the server was, and then we pulled all of her slips,” the manager tells WTAE. “We tried to go through and get as many of the customers’ names, numbers and call them and take care of it and refund them.”

After being fingered for the scam, the waitress reportedly fessed up to her crimes. The restaurant believes that around 20 customers’ bills were affected by the bogus tips.

The manager says changes have been made to restaurant procedures that will hopefully prevent this from happening again.

“”We go through all the slips every night just to make sure nothing is fishy,” he explains. “We just really didn’t expect one of our workers to be doing that, but when it happens, it makes you aware. Nobody should have to worry about it again, coming here.”

[via Eater]

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