This question is hard to answer with either yes or no. Yes, for the reason you mentioned (provide a livable wage), and yes because it puts limits on the free market which might otherwise drive everyone's wages down (could this reverse inflation?); but no minimum wage laws are not beneficial because there are people who don't need a livable wage (most teenagers, for example) and they benefit from the structure of a job and from learning responsibility, but they may not be ready for a job requiring a certain amount of responsibility - and that low-responsibility job may not be something an employer thinks is worth the minimum wage.

If I had to pick a side, I'd say yes they are beneficial. But I'm interested to see where this goes.