Imagine you're working in public space. To take a break you have to pack up your laptop, power adapter, water bottle, phone, headphones, go put them in a locker (or just carry them), visit a wc, eat, take a break, go get bag out of locker, find another place to sit with power, set up computer, power adapter, etc.
It's a lot different than just walking away from your desk at home for 5 minutes to relieve yourself, grabbing a banana, then getting back to work.
I hate working out of hotels when I'm traveling for business, so I usually post up in a library, or coffee shop. I also end up doing spending a lot of time in airports where I have to be able to get up really quickly and stow everything. After a little optimizing, I never had a problem getting up in a few seconds, walking off to use the bathroom and grab a soda, and coming back. You just can't splay your stuff out everywhere like you might at an office. It also helps a ton to have a laptop that's got a solid battery life.
Getting up to go to the bathroom for me usually mean: close laptop and slide into bag > Put bag on shoulder > holster drink bottle in side pocket while walking wherever.
It's kind of fun figuring out efficient and quick ways to unplug quickly, but it really doesn't add that much overhead, especially once it's a rote thing. I also just don't plug in the majority of the time, if I can help it.
ymmv, and that doesn't counter all the other myriads of problems you would encounter being abroad working, but at least for that little part, I think it's a pretty solvable problem
Personally I love the internet cafés in Japan - you get a private booth, free drinks, some even have showers. They're well-equipped enough that some people down on their luck even live in them permanently. I wish that model was more widespread internationally.