They do it precisely because of people who share that idea with you. Minimum wage may increase unemployment a small amount but the positive effects are ensuring that those people who have the lowest paying jobs are able to afford to live. Similarly with unemployment and welfare. For many people losing their jobs or taking a pay cut would mean becoming homeless or being unable to feed themselves.

If you think that there are enough charitable people in the world to voluntarily sustain you through the end of your natural life, I invite you to try it out.