Of course they’re not legit 
I’m a reporter. I’ve done story after story on this over the past two decades and I’ve never once found any actual legitimate charities or organisations that would in any way back it.
They are, at best, manipulators and menaces who claim to have recently been released from prison because it causes people to worry that if they don’t buy something, they’ve said no to an ex-con and may become a victim of crime.
Or at worst, casing the joint.
No homeless shelter in the land is going to make its service users go out and sell a load of marked-up pegs and dusters door-to-door before they allow them to have a bed for the night. That’s one of the most ridiculous things I’ve ever heard.
“Yes Jonny, you might be sober and not have any weapons on you, but have you don’t your J-cloth quota for the night?”
Our force tells you to immediately call the non-emergency police line if they knock at your door and they do follow up the calls and chase them out of town. The last time, they rounded them all up in their van and took them back to Nottingham (they actually did come from Nottingham this time. Though they don’t always, obviously)