It is pretty common for someone to be carrying around buckets, tupperware, or just bags full of small food items to sell for ph5-10ish. (I think thats about a quarter in US dollars.) The guy in the picture actually had two metal buckets attached to some sort of stick- sort of a balancing act.
This they said was taho. Ground up soybeans. Evaporated milk. Cooked sugar and/or syrup. (Basically my friends were just listing everything they thought was in it. Click on the link to what other people have to say about what is in it.) And sago. (The bubble like things.)
It was good but WAY sweet. Oh and it was warm, which was sort of weird because it looked like a cold drink.