Risks? I also cited actual, real benefits. How do I order my sandwich with a different kind of bread with the teenager? I don't. It's not possible. The customers behind me will get very mad if I ask the teenager to list off all 20 different kinds of bread, and to show them all to me personally too. The teenager likely will not do as I ask here, plus it's a massive waste of my time too. Ordering from humans works OK when you have a very short and simple menu so there's little chance for confusion, but this means it's quite impossible to have a lot of selection.
How about this idea: let's get rid of computer monitors, and replace them with verbal-only interfaces. How well do you think it's going to work out if you want to order a pair of shoes on Amazon.com (or any online store) when you can't even see them, and just have something reading text into your ear? Or, because you're so concerned about employment, maybe we should ban computer users from reading monitors, and require them to hire people to read stuff from the screen to them!
Finally, would you mind if I came over and smashed your car windows? You shouldn't; you should be happy, because that means someone will have a job replacing those windows.