I've worked in the fast food industry for the past 6 years. I was once a cashier making $7.25 an hour and I worked my way up to management making two or even three times the wage I was making when I was fifteen. Although I have muttered the words "I don't get paid enough to deal with that" more than enough times throughout my days working, I don't think fast food employees should make $15 an hour.
I've worked with people who decided the days they wanted to come to work. One day they would show up and the next day you would be short the only person that knew how to close your kitchen.
I've worked with people who showed up 20 minutes late for their shift. I'd ask them why they didn't call me to let me know and I'd get some variation of the response "I didn't know I had too."
I've had to deal with employees who wouldn't put their phone away to take a customer's order.
I've had to deal with many people who simply didn't care. They didn't care about their jobs and they didn't care about the stress their lack of caring was putting on their coworkers.
I'll admit, I've asked for raises working in fast food, but I also cared about my job. When I would come in for my 10 hour shift, I gave my 100% the entire time.
I've had customers pull my hair and cuss me out over a dollar sandwich. I've had a pop machine explode all over me. I've had to deal with a boss who sat in the office for hours while I had a lobby full of unhappy customers.
Those individuals that have absolutely no work ethic should not be rewarded with $15 an hour. To me, it doesn't matter what your job title is or what industry you work for, those people who come to work and give their best effort everyday without being asked deserve to be paid top dollar for their time. Those individuals who want to educate themselves and be better deserve premium pay.
In the end, if you have minimum skills, you should get minimum pay.
Instead of pouring our money into paying people more per hour, we should focus on making education opportunities and advanced career goals obtainable for everyone.