I've seen the insides of charities first hand. They weren't 'useless' charities at all but the bigger ones do seem to hit a point where they somehow go corporate - even if they're populated purely by volunteers.
I think some charities' fundraising and advertizing get taken on by former businesspeople who volunteer and adopt professional advertizing and fundraising techniques - or at least trained by them. Obviously when a charity gets really big, it's not volunteers, it's professionals.
The smaller organizations seem to come out unscathed as they don't go down that route. However, those that do, for me, can't help but lose some of their character.
My happiest memories of helping out at a charity have been the one where it was almost anonymous to the public and to it's clients. No notice, no sign, no desire for praise or acclaim. The founders' wonderful personality sold it to supermarkets to donate the food that was about to go bad (the charity was a mobile soup kitchen). Happily, the stores really didn't want the fact that they were donating the food - I can't quite remember why, but it made sense. Our unmarked vans didn't have the charities name emblazoned on the side (they were very vanilla in fact) nor did we have the donor's names.
The people we met appreciated our down to earth style and said it contrasted with local church soup kitchens who expected everyone to join in with a large prayer service before the meal was served obviously as a missionary work.
The experience still keeps with me, I saw many sights, plus I've had my own brush with homelessness too. But that was, thankfully, a long time ago.
I hope this helps 🧡