The point on Wogan is that the charity doesn't pay him anything to front CIN - his fee for the evening (over £9,000 the last time he was paid it) comes from the BBC - not bad wages for a night's work! He was the ONLY person paid a fee for being on the show. So the charity didn't invest anything or lose anything. Surely Wogan makes/made plenty enough from his many BBC TV and radio shows - money that ultimately we all pay - without getting £1000 an hour in the BBC's big charity event.
Most people would, if a fee was paid, donate that fee to the charity effort - especially if their job happens to be to ask the people who pay his wages to "dig deep". Even more so when he is someone on a salary astronomically higher than the people he is asking to "make a difference". Vile man.