BTW, you probably know this, but just for HN: some of the vendors and shoppers will be calibrated a bit differently than average, so there might be miscommunication, or awkwardness, or different conventions, to get past.

A few years ago at Swapfest, a friend and I met up there, as vendors were packing up, and one of the vendors in the parking garage was having trouble starting their truck, dead battery. So, maybe because my friend thought the vendor might be averse to asking for help, she quietly went and asked another nearby vendor with a vehicle, if they could give a jump, and they cheerfully did.

(Friend is a former military officer, who had also gone to MIT, and who exemplifies some of the best of tech industry leadership, including Knowing Your Nerds.)