Yes Publix works with Instacart, I actually shop and deliver for Instacart. I don't know about subs, I have gotten deli meat and cheese for a customer.
Publix works with Instacart for pick up and delivery services, so it is offered at this location. They have their own app with Instacart just for these services. You can also pick up deli items ordered online inside the store (like subs).
Only pick up subs etc not a delivery available place
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