u/Massive-Review9065

To simply put: shoes can act as a context cue. If you normally take your shoes off when you're relaxing at home, keeping them on can make you brain feel like you're still in “doing stuff” mode rather than “couch mode.”
It’s kind of like changing into work clothes (except I don’t work).. Let alone, this works for people who study in completely different spots. You can move from one place to another without any hassle. Balcony, the kitchen, wherever. There’s something incommunicable about the feeling of being dressed all the way through. So it can be fairly useful than being completely barefoot.
So ya, as long as your shoes remain intact on your feet, it also remains a psychological trick: shoes = day isn't over yet.