Fake petition on the streets
This happens a lot in Lisbon. Couple people asking donations to help children or animals. Most of the time they have couple stuff to "give you" if you give them a donation. Key chains and stuff like that. You are nice and think you are helping someone but these guys are working for a company that orders this shitty keychain and similar stuff in bulk for couple cents apiece. The sellers make money too. They share the money with the sellers. These scams happen to everyone, even Portuguese people fall for it every day.