Uh I didn't really think about supermarkets in Paris, or look for them. But forgive me for my use of the word "tiny", everything Europeans shop at is nano-sized compared to what I shop at in Texas. My grocery store is like the size of Berlin train station.
Yeah I'd imagine they're not as huge as the one in the US.
But keep in mind that service is not as big in most european countries as it is in the US. But everything is done to have at least the minimum of what you need at any given time. You just need to know it exist. Restaurants closing late, small supermarkets open all night, pharmacy open all night too.