Lead Tokens

I seem to find these on a regular basis and yet I have friends who have never found a single one.

The lead tokens I suppose are a bit like the modern bonus points at certain shops, whereby you can only spend them at the shops you get them from. Each token has a different design for different goods sold. Also at that period of time there was a shortage of small change and is the reason why tokens were allowed.

I wonder what the people of those days really thought about lead tokens, or do I already have the answer with the number I find in the fields.