It's not unusual, you'd find most of it in my home now that phones add a charting device.

The Brits on RUFFIAN each had a laptop, a spare(not unusual, an upgrade), a tablet, a modest onboard chart plotter, iphone or two with a chart app, and maybe an old gps pocket with charting. He was in the tech field but I don't find this stuff too unusual in my world. They had all this stuff already(standard gear for people their age), all the paper charts would have cost them more I'm sure.

You should be uncomfortable without charts if your electronic charting is served by your ships batteries. That's too risky.

People comfortable with just electronic charting have redundant gizmos running on their own batteries, they're own programs(chart apps can be free!).