availbility of electrical power at towns

for my next P.C.T section(s) hike, I'd like to try guthook/cellphone instead of my dedicated G.P.S, for electronic navigation .. this requires me to take a "power brick- which will force me to use available e.power( typical 110vac-wall outlets) at stops along the way. and I want to ask those in the know if carrying a "plug in converter"(typically a plug in cube that has a usb outlet built into it. is this even necessary? these days with heightened reliance on electronics at stops a USB outlets will, already be in place in place since it seems most hikers carry a lot of electronics, these days. this should allow me to avoid carrying plug in cube voltage converter at home. not a great weight savings, but, something to help offset the weight gain of the cellphone along with power brick over battery GPS I currently carry.

I would not count on usb plugs being ubiquitous. They are pretty common bedside at nice hotels, but I wouldn't count on it at small motels in the back country and certainly not outside a motel (restaurants, gas station).

*edit: I saw advice somewhere that suggested having a small splitter in case more people are trying to use an outlet than plugs available.

Something like this: https://www.amazon.com/Extender-TESSAN-A...0NsaWNrPXRydWU=