Restaurant scam in La ramblas
This is more advice than scam information. Avoid restaurants in La Ramblas and other really famous tourist spots in Barcelona. Usually, these restaurants have to pay really high rents to have the business open in such a famous spot. So what's going to happen is that they need to increase their prices (and or) reduce the food quality if they want to keep the business running. So there a chance you gonna eat low quality Spanish food at really high prices. This doesn't mean that every single restaurant in the area is low quality but you know what to expect. Be especially aware if the menu is just in English and not in English and Spanish. This usually means that they don't expect Spanish people to eat there.