I think the domain is limited to what the keywords naturally limit it to "Charity Cup Cakes".
Usually charities have their own website and run various/many events through them not just limited to cupcakes - raffles, tombola, games etc etc. That's not to say some charity or organisation wouldn't want it, but generally speaking they don't have high commercial budgets, hence "charity" so that may well reduce the potential sale price.
Sorry but I think the keyword "Charity" in the domain ruins any chances of a non-charity commercial potential. Would you want to run a store or shop with the word "charity" in the name if you are trying to earn a living etc?
I agree, and think the best use of the name would be as a website providing information on "cup cake" related events for
various charity organisations and even local people raising money for charities by selling cakes etc. Such as a fundraiser website (but not for one specific charity body or organisation).
This is possible, but there won't likely be an end user sat wanting to do this, so might have to make it a project yourself.
As always in domaining, funny things can happen and someone out there might like it, even another domainer, so you could sell it. However such things are very rare.
Best of luck