Here's the issue, I think (as discussed in a sibling comment): If you're right about them being a student, it's pleasant small talk. If you're wrong about the

Here's the issue, I think (as discussed in a sibling comment): If you're right about them being a student, it's pleasant small talk. If you're wrong about them being a student, you may be highlighting the fact that they're in a dead end, low income career path. The second case is sufficiently painful and likely, that it's probably a bad idea to lead with this question.