Slavery? Waa??
Not all jobs are worth the same pay. Why should someone be able to work a frontline McDonald's job and support a family and buy/rent a nice home? That's not a job folks should aspire to, unless all you are capable of is working the fryer. It's an entry level job for students and those on their way to something better, unless you get promoted into management and make it a career.
I'd rather we concentrated on funding and encouraging college and trade educations for folks so they didn't get stuck in McJobs. It's better than forcing employers to pay more than some labor is worth.
$15 an hour is basic, ground-level, keep the god damn economy from collapsing pro-capitalist policy.
If someone can go work a fryer for $15 an hour, they aren't going to go out and educate themselves on student loan debt, and then cram themselves into an ambulance and save your life when your heart stops for $16 an hour. Which means that EMS companies are going to have to pay substantially more than $15 an hour if they want to continue functioning in this here economy. Same as almost every other job that is an absolutely necessity in a functioning, first-world economy.
$15 an hour drives up everyone else's wages. And as it's clearly fucking obvious now, JobCreators™ aren't going to go out and pay their workers living wages without being forced into it.
So, you can either play some goalpost-shifting abstract jerk-off game in which we talk ham-handedly about how we're going to "encourage people to not be fucking poors", or we can start paying people a wage so that even the god-forsaken poors are able to pay rent, purchase non-shit-tier "food", and give them healthacare. Like every other western, 1st world country on the planet besides the US.
I'm all for a $15 minimum wage, because it would, obviously, raise my per hour pay, as it would everyone who works on the books in this country.
In case you've missed it, workers received their highest pay and benefits way back in the mythical 50s. You know, when the highest tax bracket was right around 90%. Go figure.
US industry will either be forced to pay workers a fair wage, or they'll pay a clearly-unfair wage because, like, pull up your boostraps and stop being poor you gross poor!
There are dozens of 1st would countries with modern economies that show how this works. There are zero first world economies that use remotely similar US economic policy that function the way US conservatives have promised for 40+ years that the economy will function, if we just give rich people all of the money first.
Go figure.