I use the wireless Apple keyboard and trackpad, which both have similar battery lives, but when the battery runs out it always somehow happens to be right before a meeting where I really need to plug it in and use it right now

(and these days when everything else is USB-C, instead I'm scrambling to find where my damn lightning cable has gone)

Although I get why they would not put the port on the back - their Lightning cables are not built for the repeated motion/strain of a plugged-in mouse. Anything more strain than plugging your phone in and setting it down causes the cables to break down in months.