There's a Walmart by us on Constituyentes. Having moved from Las Canitas where we shopped at Jumbo to Urquiza where we shop at Walmart, I can say that in Argentina is more like a normal supermarket here than the couple I've seen in the States. Basically like a slightly lower class Jumbo. It's not crazy low class redneck obese-chair riding walking around in their underwear craziness that you supposedly see in the USA.
The Walmart on Constituyentes has a full produce section (with mangoes! and cherries! and imported fruit! and wheatgrass and alfalfa!) They have a small organics section. They have a well stocked liquor/wine section. The quality of meat is also surprisingly good (I never thought I'd buy meat from Walmart, but it's good quality). They don't have much in the way of import foods anymore, but hey, neither do most places.
They have a clothing section as well, I think they sell that Ropa Para Todos. The clothing otherwise is exactly like the stuff they sell at Jumbo -- though it looks like Walmart brings in all the Disney licensed kids clothing (like the actual stuff, not the rip off) so I've bought my toddler a few pairs of disney underwear / Marvel socks etc. There's whole sections of Walmart that I haven't even wandered into (toys, furnishings, etc).
So if you want to see shocking, I wouldn't bother with the trip.