(I think it's still named that) There's also a second market across the street. We used them both from Lake Tashmoo to stock up with a family of four two years ago. That's where the islanders shop for grocerys. We rented a taxi to haul it home, it was worth it.
The small market near the ferry in Vineyard Haven is pretty good. Can't think of the name.
We didn't see that Shop and Go outside Edgartown. All we found were those awful foodless markets that sell junk food.