Well, it's obvious that they can't target walmart, and since it's been decided that it's not unconstitutional to pass minimum wage laws, then why not do it properly? Or are they?
Surely that shit is defined somewhere. Look at the statutes and associated materials. If it's defined as "minimum level to appease apathetic public; the tipping point for what they would accept" then it's probably fine the way it is. Or not. Couldn't you just raise it?
And according to wikipedia, 5% report income below min wage, which is sure to increase as the wages increase, so maybe min wage laws aren't the answer. Just work 2-3 jobs I guess. Oh you're already doing that. Well then shit's sorted.