ANTAKYA, Turkey — Wars, as businessmen have recognized for centuries, can be very profitable. Evidence of that is on display here, where a half-dozen military supply stores in the center of this town near the Syrian border are busy catering to a clientele flooding in from all over the Middle East.

Exactly where the shoppers come from, the store owners say, is not their business.

“Look, we don’t ask our customers their nationalities,” said Tayfur Bereketoglu, the owner of a store bearing his name. “But they have long black beards, they don’t speak Turkish, and the reality is that there is a war next door. Why should we ask where they’re from?”

The new customer base, as most everyone here recognizes in private, consists of foreign jihadis, mostly Sunni extremists drawn to fight the Shiite-aligned government in Syria’s increasingly sectarian civil war. The foreign fighters, easily spotted because of their bushy beards, enter Turkey through Istanbul, land at the airport in Antakya and slip into Syria, though not before doing some shopping here.

The stores cater to the needs of the fighters coming here for the first time or coming out of Syria for air: military vests, camouflage pants, knives, gas masks, prayer beads, brigade banners, solar generators, telescopes, binoculars, flashlights, not to mention razors and shampoo — pretty much everything short of arms, which are waiting for them in Syria.