I don't think Massey does delivery. There are two, the original in the old mall and Massey Gourmet in the Baywalk mall across the street. They are a short walk from the dingy dock, and Danny who works the dock, will bring your cart back for 5 or 10 EC.
Alternatively could taxi, bus, or walk to the store and grab a taxi back, they are readily available, should be $12-15 US.
In Baywalk mall there is a duty free shop where booze is slightly cheaper than the supermarket (Chairmen's Reserve $11 US) you need your passport to buy.
Beef is expensive in the supermarket but there is a place up towards Cap Estate that sells to restaurants and the public. Dan got ribeye for 47 EC a pound, cut to order from a frozen whole piece. Fresh (?) strip steak is 198 EC a kilo. You could ask one of the taxi drivers at the marina.
If on the way from the airport you pass the Cul De Sac thete is a shop that sells steaks and seafood even cheaper, I don't know the name but their sales were coming up on my feed. The taxi driver may know.