Brought to you by my discovery that some people think that “the customer is always right” isn’t the slogan of a long-dead department store, but rather it’s an actual call the cops law.
At least in Germany that’s the case.
Every contract is legally binding in Germany, even verbal contracts or in this case price tags (to some degree). Obviously other laws may invalidate them and verbally is hard to prove. For example if you advertise onetime off prices for a week to lure people in the store you have to have a reasonable amount of these items to be available through the week, otherwise people are eligible to get the offer or compensation.
Adding your own sticker would probably be fraud and easy to prove for the store (not matching sticker, no plans to reduce prices, …).
Every contract is legally binding in Germany, even verbal contracts or in this case price tags (to some degree).
This seems to be contrary to what I can find. A price tag is not a contract but an “invitatio ad offerendum” so an invitation for the customer to make an offer at the checkout. Then a contract is created when the cashier accepts this price after scanning it and matching it with the price in their system. Therefore it’s not the price tag that counts but the price in the cash register. I could be wrong or the law has changed in the last 1-2 years, but I found this information here (sorry they are all in german):
https://www.mdr.de/ratgeber/recht/preisbindung-supermarkt-regal-kasse-100.html
https://www.test.de/Verbraucherrecht-Regal-oder-Kasse-welcher-Preis-gilt-5115345-0/