Why was I allowed to do this?

Im a Gringo. And one day I walked into the Josefina Mercado Latino to buy a redbull because I didn't feel like walking across the street. I walk in and the place smells like beans. I paid for my redbull and nobody said anything to me. I don't know if it was because they didnt speak english or they didnt realize I'm white. The cashier lady even said hello. I was nervous though on the inside, Ive never been around that many people before I wasnt culturally or ethnically equal to. No one stared or even said a thing. I was expecting whispers in spanish and rapis glances, but no. They didn't even have a sign that said something like "Cuidado, no queremos Gringos aqui" in the window