I think the benefit isn't about laziness, its easy of access / ubiquity.
Having these devices in coffee shops, airports, cars etc, allows people who don't have a charger with them to charge their phone.
We have all had this issue, and the fact these are selling whatever format is proof its a helpful service for customers wherever they are.
Ie what if you're in a restaurant and your phone dies? It's happened to all of us right? Or the airport, or a football game?
Wouldn't it be great if seats at a stadium had these built in?
I ALWAYS have an issue when traveling. If you're in an airport for hours what do you do? You get on your phone and surf. 2 hours later (if you're lucky) your phone is dying. Do I have my charger in my carry on? Can I find an outlet? etc etc...
I definitely see the value proposition here