Just Giving is a successful digital start-up: a limited company, with owners including founders and investors. It’s not an charity and it’s not evil either. With £20m revenue pa and fast growth, investors are no doubt expecting a good valuation at some stage and an exit. 5% is not a big fee for their services: they have been plugging away at this for >15 years and made it much easier to give. If the founders pay themselves market rate salaries and they and their fellow shareholders also get a good return on the investment they made (in the case of the founders that will probably be many years of worry and hard work) then good luck to them. They will probably sleep easily with any capital gain they make and the world will be a better place for what they have done. (I have no relationship with the company).