Honestly I don't have a problem with it...... this area is impoverished. Sometimes people use a restroom and take baths(bird bath).. if you don't buy food and need to use the restroom just go to the counter and ask. In the city you need a coin to open the door...
There are a lot of bums and beggers that hang out here and the Bola Market Gas station across the street, locking it is to keep them from bathing in the sink.
I agree with Di Roc. Look at it as a courtesy. This also means they know who's going in, looking like "what".....
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