Depends what that $100 was going towards. If it was going towards for example something unnecessary, or staff payments then It'd tempt me. If that $100 was genuinely going towards a good cause for each of those charities e.g. money being used to provide necessities for poor people, or for research going into serious illnesses such as cancer, or to help against animal cruelty then I wouldn't take a $1 off anyone. If I genuinely knew the money was not going where it should be, I'd consider taking the money.
Anybody who thinks of touching someone else money or looking for a handout should be ashamed of themselves. Hard earned money gives youa good life and -a fulfilled heart.