When I first got my dog, I'd get frustrated with her when we went to the park and she wanted to sit under a bench and I would try to encourage her to run around. One of the more experienced owners told me very kindly, "the way I think of it is this - this is their time, to do what they want. And if they want to sit under a bench, or chase a ball, or take a nap, it's up to them."
With my male BP, every handling session he's around 50/50 on "exploring and doing things" or "finding one of his favorite spots in my room and taking a nap" and I try to let him do whichever he wants and let him nap in my bed if that's how he chooses to spend his out of tank time.