Out of interest, I've just searched Google for
"jumble sale", "ipswich" "2022".
Several came up in the results, both past events and forthcoming ones, for Ipswich and surrounding towns and villages. Every single one of them seems to say "[i]Scouti] Jumble Sale", indicating that it's largely only Baden Powell's lot that's running them these days.
I'm a terrible hoarder, so not as much finds its way to charity shops as it probably should. However I have had some strange gifts over the years, such as a set of sash window locks when my house didn't have sash windows!