MaizieD we don't know if all the money went to charities. I'm sure that many royal supporters will pop up now to tell us that of course it did, but we don't know. We don't know how the money was earned, or if it was the sheikh's own money, or if he intended it for Charles personally, or if he wanted it to support the Princes Charities. No obvious favours? I think the operative word is "obvious", isn't it?
There are rules about accepting charitable gifts from anyone, especially cash worth 3 million Euros.
A person/charity must not just be above board, they must be seen to be above board. Does anyone have the charities' returns for that period? How is the donation accounted for? How are we meant to know that the amount in the Fortnum and Mason's bag is the same amount as was donated to the charity? How do we know that none of it went astray between carrier bag and Coutts?
If you or I were running a charity and got a few million pounds donated, we'd be under intense scrutiny and we'd be telling people, no more bags of money please, let's work out how to do it transparently.
At the very least its naïve of the Prince to accept repeated donations in this way. "Giving offence", really? Its not the middle ages any more.