Italicized thoughts?

Lately, I've read a dozen or so screenplays from contest winners and/or recent college grads. Nearly all of them have one strange element in common, something I've never seen before: writing out thoughts, or odd prose (i.e., NOT observable behavior) in italics. A made-up example to illustrate:
"John Q. Protagonist shuffles along the sidewalk, oblivious to the heavy pedestrian traffic around him. (italics)He has the weight of the world on his shoulders and doesn't know who to turn to.(/italics)"

I feel like this stylistic choice has to come from somewhere specific. It's odd to me that they're all writing similar non-observable behavior and they're all putting it in italics. I've seen this kind of internalized behavior written in scripts once in awhile since I've been doing freelance reading (about a year), but it's never been italicized. In these contest/college screenplays I'm seeing it all the time, always in italics.
It's odd that these writers aren't coming up with visual ways to illustrate the characters' feelings; instead they rely on what I've taken to calling on-the-nose action blocks. In addition to being lazy writing, they're often redundant, spelling out emotions or ideas that are already obvious in the context of what's happening in the screenplay.
Does anybody have an explanation for where this "style" came from or why these writers think it's necessary or useful to add largely useless information in italics?
~Stan