Have u encountered with a person asking u whether u would like to make a donation for unfortunate or not?

I have faced it few times and i rejected them because i think that they are swindler.

This afternoon, a girl afternoon approached me and said they are having a donation running.
She asked me whether can make a donation of rm10 or not
I didnt turn this volunteer down this time.
I took out rm10 and gave it to her without thinking much.

Was wondering whether that was a true donation running or just a swindle.
At least, i donated with a heart of helping those unfortunate.