My conclusion is that the idea that everyone should give to charity is wrong.
How many people here actually think that, with no regard to income? (Edit: i.e., think that everyone, no matter how low their income, should give to charity?)
Probably no one. What I mean to say is something more like: If someone works in cancer research, and cancer is a valid charity, then asking them to donate to charity is equivalent to asking them to take a pay cut.
The number of articles on LW about how to give to charity suggests that people think giving to charity is the default state, and/or that not giving to charity should give you a karma hit. Whereas I think something more like: If you're giving money to charity, it's an indication that you have chosen for your profession work that is not directly helpful to others, and are making up for that with the money you earn at your hopefully more-profitable profession.
If you think that SIAI is the best charity, and you work for SIAI, should you give any money to charity?