Experienced this first hand. Quirino Ave, going to Roxas Blvd. At the interesction of Taft Ave, this taong grasa looking person suddenly appears on the driver side after spilling something on my vehicle, dunno what really, and mumbles about being hit, and how his groceries or what he was carrying are now useless, wanting to be compensated.
It took me a few seconds to gather my wits about and process the situation and react by telling the guy point blank that he was scamming me.

Gave him one hard look, closed my window, and just drove away.
Sa ganitong mga modus, dapat huwag kang unahan ng takot. As long as you know/feel na hindi ka mali, tatagan mo loob mo.