Blogging for money

I was looking at a blog today and in the margin there was a link where you could 'Donate' then it listed the options for payment. I totally understand people putting ads on their blogs and reviewing products for various companies. Trust me, I'm all for making money, but just putting a 'Donate' link on your blog seems a bit bold. The writer of this particular blog was not raising money for any sort of charity other than herself. After reading some of her posts I didn't get the impression she was hurting for money. Has anyone ever donated to someone like this?? Am I the only one out there who thinks this is a bit rude??