Yes about the salt but never heard of them together sorry
Market Basket has good people working for them. Ask any one of them and I know most of them will bend over backwards to help you.
I have never seen salt and vinegar powder there, but I've never really looked for it either. I would say to call the store and ask. They are usually very helpful.
They have salt but, maybe vinegar powder if they do it would be in the cultural section.
I know thwy carry salt but not sure of vingar powder.
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