Have you ever seen shaved ice peddlers selling out of shopping cart and trash bags?!

I live in greater Los Angeles area. Once a day there is a guy passing around with a shopping cart full of black trash bags and uses a bell while he passes by our apartments. I thought he is just collecting cans or so but I just saw him emptying out water from those trash bags. Then a woman came to him and he did some shaving motions inside that trash bag lying on the top of the shopping cart, where a child sits, and then took a foam cup, put something like shaved ice from the trash bag into it, put something from a bottle, inserted a straw and gave it to a woman, who paid him. He then went on his regular patch ringing a bell.

I am confused - could this be that this man is selling shaved ice out of the trash bags and shopping cart? I only saw him from the window across the street, but this is what it looked like. Is this at safe? Aren't people afraid to eat something prepared in such conditions? I previously saw only the Latino ice cream vendors pushing little carts, but all ice creams were packed and the cart was refrigerated or kept cold inside - not in a cart taken out of a grocery store with ice in trash bags. Is this homemade shaved ice common in Central/Latin America (since we have a high population of Latinos here)? Just curious :)