There are snack bars on the ferries, not surprisingly, but "Turkishness" presented itself regularly as emissaries from said snack bars were constantly circulating around the various sections of the boat with typical Turkish offerings to assuage your hunger or thirst. One go-round would see a tray of the traditional tulip-shaped glasses of hot Turkish tea; the next might be fresh-squeezed orange juice or bottled water. Then a few minutes later you might have the opportunity to grab a simit, a fragrant golden brown bread ring covered in sesame seeds, one of the more prominient street foods of Istanbul.
In addition to these "official" roving sellers, on the longer trips there were additional items that appeared as if by magic, from fellow passengers. One fellow had sets of fruit knives he was selling, and did his schtick before the captive audience; the knives' sharpness impressed sufficient passengers to evidently make this variation on the "traveling salesman" method worthwhile. At other times we saw abaya-clad Muslim women selling garments which they toted in giant nylon carrier bags; one appeared to be plying the ladies with various sorts of muumuu type loungewear or nighties. One Turkish woman sitting across from us bought not only two nightgowns, but succumbed to the knife-hawker as well.