Kwajalein Island has US military dining facilities, a convenience store, and a small supermarket available to base residents and authorised guests. The facilities are functional and well-stocked by remote Pacific standards — the US military supply chain ensures that.
None of this is accessible to independent travellers without official sponsorship or a base access pass.
On Ebeye, a short ferry ride away, there are local food stalls and small shops selling packaged and canned goods. Local Marshallese food — rice, breadfruit, fish — can be found here, and prices are considerably lower than anything on the American base. Ebeye's food infrastructure has historically been strained by the island's extreme population density.