1) I agree with many below - this isn't a "Target policy," but rather something that should be common sense. I don't think it really would be worth it for Target to post a sign, because 99% of people would ignore it anyhow, and still balk if an employee called them out, even with the "policy" posted in plain sight.

2) After reading through all the comparisons and comments about theft below, I have some thoughts. The big thing that struck me is that people seem to have different opinions as far as "how much reading is too much" prior to paying for the magazine.

To me, if you flip through it, maybe peruse the table of contents and a few pages to get a feel, you're fine. That's similar (as some said) to reading the instructions on a box or briefly trying on a garment.

However, if you stand there for more than 5 minutes, obviously reading and absorbing the material, then leave without paying, you now have that information in your brain, but did not pay for it. Which, to me, is kind of stealing.

The other thing here is that the manager / employee had no way of knowing if the OP was going to pay for the magazine in the end, or was just going to stand there all night reading and leave without buying a single thing.

If the manager was outright rude, then the complaint should focus on that. What he told you, however, was nothing that should have come as a surprise, or is worthy of a complaint.