I have had this argument endlessly with my brother in law. Charitable donations are no substitute for what the government does. There are several
reasons.
1) People aren't as generous as you think they are. They will keep a portion of any taxes saved rather than donate it.
2) People give to the causes they care about. This is not always consistent with where the need is. Often this is to religious institutions or things that directly affect them.
3) When times get tougher and more help is what is needed, that is when people give less.
4) Charities simply can't do what government can do. They are great at filling in holes at the margins, but they don't have the scope to deal with bigger issues. They are also not coordinated to deal with bigger picture issues for more lasting solutions.
5) People prefer charities because they think government is wasteful and inefficient. I promise you most charities are worse. They have great intentions, but not the skills to be efficient. Government has improved dramatically (mostly because funding has been choked off). It will never be perfect, but neither are private institutions.
It is just a fallacy (a hopeful one, but a fallacy nonetheless) that charity can take the place of government on these things.
