Depends on the grocery store. If you shop exclusively at Target, a company that caters primarily to those who ‘prepare’ as opposed to those who ‘cook’ you’ll find less healthy options than actual grocery stores.
That depends a lot on the Target. One location around me only has a very small produce section for their groceries with everything else pretty much being prepackaged products. Another location has quite a large produce section along with a deli, a butcher counter, and a bakery.
In my travels I've found even the size and quality of the produce sections of SuperTargets can be quite variable.
But yes, I do agree their range of choices for fresh food products is usually more limited compared to good, actual grocers. But that applies to their packaged goods as well, they often don't have as many choices of lots of things. I might find almost a dozen brands of pasta at an actual grocer but only have three or four brands at Target. To me it seems the ratio is about the same, its just the scale is different.
And to be honest, its the same story for practically all the stuff at Target. They don't have the widest supply of craft supplies compared to craft stores like Michael's and Hobby Lobby. They don't have the widest selection of bicycles compared to the bike store. They don't have nearly as many toys as what Toys R Us did. The book section is smaller than a Barnes & Noble. What else is new.