There's specific ways people like to get involved and show support with charities which are back handed.
My charity for example always gets people wanting to donate items, and people get incredibly angry we decline them because they aren't suitable (we can't take duvets for example as the animals we have can't have them, they aren't washable and it's a nightmare). People want to volunteer but only for a day or odd weekend ignoring the actual skill involved and the amount of staff time that would be wasted getting someone for just a day
People are willing to donate items but dont give actual money (which is more needed for things like meds, keeping the lights on, and staff costs). We can buy a certain item from our wholesaler for a half the cost, but because of not wanting to give money instead we get smaller versions that people can buy themselves on amazon for twice the price
You can see that in things like operation shoebox child where people will spend £10 on filling a shoe box, companies will pay to have it shipped across the world, there's lots of people involved in distribution that costs more than the box contents. However people wouldn't give that £10 for people to chose things to buy in country and support the economy of that town
I used to live abroad near a charity where people would fundraise thousands of pounds to go to the country and help build a school. As part of doing it they made a few hundred pound donation to the school but 90% was based on getting someone with zero construction skill halfway across the world to shoddily build the wall.
The charity needed that few hundred so was happy for the rest of it to go by the wayside, then use the actual money they got to employ workers to build a safe wall that was structurally sound.
They knew that people needed to feel emotionally connected to it, and would never give that money without getting something for them selves