Doing this is stupid and deceptive. Just do what everyone else would do and raise the price of your items. There is only one reason any business would do it this way. And that is to make things look better than they are. Yes- It is a deceptive gimmick. Just like when a business charges unreasonable shipping and handling fees to cover a low product price. Same level of slime.
How is it deceptive? They tell you what they are doing, and then they do it. I have been in several restaurants who now charge 3-4% extra if you use a charge card. They are passing the fee they pay the cc company on to you, but you can pay cash and avoid it.
Years ago, a club I belonged to held its officer installation at a local restaurant. Members would pay separately, but the restaurant was going to give a 10% rebate back to the club. Some people arrived early, and the wait staff asked, “would you like a beverage?” Most people did.
At the end of the evening, the wait staff handed the treasurer a bill for the drinks people had at the beginning. There went the rebate. Now that was deceptive.