Me too! I have spares for mine and can take two spare charged batteries with me if needed, a lot easier than trying to find a mains socket in a strange work place that's not secure or you can't always see your phone from where you’re working.
Not an easy design change when phone has been built to be (somewhat) waterproof and back is glued on.
Would be nice if they did. Replace glue with nice rubber seal and some small screws. Not going to happen though.
As for the charging in strange places, there are solutions like this which will charge your QI device (like Note 7) and one or two other ones via cables.
Disclaimer: Not actually tried that, but tempted due to similar reasons.