@ Spleen Cringe.
I think you hit the nail on the head there?
"kids earning a few quid raising money for charity"
Yep, for the most part (in my experience) no interest in the charity on their tabbard, just turning a few quid and expecting people to hand over personal details so that they can do so. Part of the reason I despise them.
I had a young lady of about 21(ish) "representing" Children In Need block my path complete with painfully fake smile and well worn opening lines. Personally I do a lot of work with Children In Need locally and when I asked her what projects the money would fund she was clueless. When I told her absolutely truthfully that I don't have a bank account (cultural thing, long story) she got very stroppy indeed and accused me of lying. I could bore you with other similar stories but won't. And yeah, despise (as opposed to hate) reflects my opinion, which is what I was giving in regard to the OP.