In much of the rural US, it’s easy (ask folks which farmstand they go to). In cities, it’s also pretty easy (asian or mexican grocery for non-organic, specialty produce shop if you want organic). The problem is the suburbs. Don’t live in the suburbs. If you must, get veggies at the farmer’s market.
Every suburb I've been in has a big box grocery store with a large selection of fresh produce. If you want something specific you might need to go to a specialty store, but there are plenty of vegetables where people buy groceries. You won't find them at gas stations, but nobody buys groceries at gas stations.
As identified in sibling posters, the issue with these vegetables, in as much as one exists, and speaking very broadly, is that they look pretty but are flavorless.
> On top of that, the tomatoes you see in those supermarkets have been bred for high yields and durability, not flavor. "As a farmer once said — an honest farmer — 'I don't get paid a cent for flavor,'" Estabrook says.
Which shops? That's true of the big chains (Safeway, Trader Joe's, Costco can be hit or miss), but you can get ugly-but-great-tasting fruit in plenty of the local produce markets.
What I meant to say was “as convenience food” as in already cooked and not a salad. Plenty of good stuff in stores, but not a lot from the available quick food places