Akshay asks me:
Given that there are more coins and coins are worth more in London, with gbp1 and gbp2 coins, would you expect panhandlers to do better or worse? I would guess that people are less likely to part with their change and give it to beggars, whereas in the US people generally hate carrying around coins… And they are worth a lot less.
On the other hand, when they do get donations, the amounts are probably higher.
You can ask a comparable question about tips. In the Eurozone, one works pretty hard to avoid a steady accumulation of coins. The twenty cent piece feels worth less than does a U.S. quarter, because it competes for pocket space with the one- and two-euro coins. My intuition is that, adjusting for the size of tip or donation, in Europe or the UK small-denomination transfers are more common, which means that people with lower values of time end up sorting the coins.