"More money would be collected (especially if the stewards were proactive in collecting)"

I believe it is actually illegal to rattle a collecting tin or bucket. Apparently it counts as intimidation and/or begging. There was a long discussion about this in Sidmouth many years ago, and I beleive the law is unchanged.

You are allowed to stand still and look appealing and to hold out the tin (or bucket) but not rattle it or ask for donations.

As with motorhomes parked all the way up the Bickwell Valley or amplified music at various places, the law is never likely to be enforced in FolkWeek, but that is the position as I understand it.