He's right, but it's hard to have much sympathy for business owners like this. Once "self-serve" became the standard operating model for gas stations, many good business practices got thrown out the window. Once you have your customers handling your business equipment, all bets are off.
Check out the cleanliness of the counter behind your local Dunkin Donuts or Starbucks, and then compare it to the self-serve coffee counter at your typical convenience store. The difference is stark.
If burning the American flag is considered 1st Amendment “political speech” so is applying a sticker.