You could, but it would be a lot easier to just bring a battery bank. That way there's one thing to keep track of, and you can charge multiple times off one bank. I've charged my phone once and my SO's phone twice between recharges without draining the battery bank. Even if swapping batteries was dead simple, the battery bank is simpler.

That said, having the option is great! I will probably never replace the battery though, since none of the phones I've ever had needed a battery replacement, I usually run out of software updates, shatter a screen, or break the power button long before the battery is a serious issue.