Of course a very small amount of all donations goes to the work abroad. To be able to split it up and notify where your donations are being spent would be an administrative nightmare. I’m sure if someone was donating to OXFAM or UNICEF or Cancer Research and was told a month later ‘oh by the way your donation was part of our CEO’s £120k package, thanks for donating!’ The frothing at the mouth of some would mean localised flooding.
I think it depends on the charity. If you donate to a charity that says its helping clean the streets of Britain then you wouldn't expect it to be carrying out work in other countries.
I think we have to take the view of common law justice here and say what is to be expected by the average reasonable person. Most people think the RNLI use their life boats around the British coast. They are giving money to the RNLI for that reason. So when they find out some of the money is going to other countries that have nothing to do with life boats around the British coast then its obvious the donator is going to be annoyed, shocked or surprised. To act like there should be no reaction at all when you've been deceived is I'm sorry to say kinda odd. Also its being assumed these people are only donating to the RNLI. We don't know that. They might be donating to other charities that do work in other countries.
It is interesting how some people turn a good intention of donating in to a malicious act i.e. "you donate to this charity but not to that one? you hate those kids?"
I think there is a website that tracks how much of your money goes to the CEO and other expenses, as I remember a few years ago there was a scandal of how little money per pound was actually spent on what you was donating too. These charities are sadly being used more as a tax deductable route rather than the actual charity work they was setup to do.