I don't think less of anyone 'regular' who doesn't give to charity and doesn't apologise for it. There is no guarantee the money even gets to where it should and even when it does it doesn't seem to make enough of a difference. Some people in some countries are beyond help because their government is either incompetent or corrupt.
There are plenty of reputable charities even in developed countries.
Also, I'm not sure what you mean by "enough of a difference", but I think saving one person's life for a day is "enough of a differencce" by most measures.