42 made an excellent point. I know of someone who, when he gave $20 to a Mossad, it was considered a great accomplishment. But he had no problem donating $6 million to some funny project. There are many stories that indicate how one has to be Zoche to give.
Another point: It says that one who has $100 wants $200. If so, $20 has the same value to a multi millionaire, although it doesn’t translate as bread on the table. So when you hear about someone who donated $1,000,000 don’t translate that onto $10 of your own.