These aren't sneaky ways to get answers to questions you can't ask. They're straightforward ways to get the valid information you might have been looking for, if you were asking the invalid question in good faith. For instance, not "what religion do you practice", but "what days can you work"; it's fine to verify a candidate can keep your required schedule.
Flagged, because this article is old and the headline is misleading. nickb posted this same article a year ago.