Yep, a lot of small businesses are charging a 2.5-3.5% charge if you use debit or credit. That is part of what the banks charge them.
I can’t get mad at them about it. The banks are ripping all of us off with more and more fees.
Retailers used to accept cards because it encouraged business and more potential spending. Restaurants are a bit different I suppose, you know you are going there in most cases and if you know the policy you bring cash or pay the fee. Personally it does bother me and I reduce my tip from a approx 22% ish down to 18% shifting the cost to the server which is unfair, but so is charging the extra 3-4%.