Really it's the opposite. It's called a pharmacy, but in practice it is a convenience store first, and a pharmacy second. Often times the pharmacy is closed, has restricted hours, is understaffed, etc.
Today I learned another reason that despite appearances Baltimore is not a "major metropolitan area". I'm not being sarcastic, it really doesn't have the economy of one.
But I also wonder if it's just the very largest cities that have easy 24 hour pharmacy access.
Wow! I live in a city which is fifteen times larger, and there is no Walgreens open later than 10 PM (nor Rite Aid, nor Bartell); the pharmacies generally close by 8. I wonder why some places get better service than we do?