Shake, Rattle and, errr, where was I?

I went to Tesco at lunchtime. To buy some lunch. And to get some petrol for the car

[It's important to get these things the right way around: Vauxhall Tigras don't run very well on cheese & ham sandwiches, and drinking petrol makes my breath smell.]

As usual, I had to run the gamut of charity collectors by the supermarket entrance. Today there were a couple of old chaps, well into their seventies, shaking collection tins for the Alzheimer's Society.

It occurred to me that they were unlikely to make much money. Any savvy punter will be able to avoid donating: "Alzheimer's Society? I put money in the tin earlier on. Don't you remember?"

And what if the old boys forget to hand the money in to HQ? In fact, for all we know, they didn't even know why they were standing there in the first place; mid-rattle they are likely to wander off and buy some cat-food, Daz and some steradent...