It's a convenient backup, and can easily be sufficient for normal use. My friend can drive to another friend's house in the British countryside and plug an alm

It's a convenient backup, and can easily be sufficient for normal use. My friend can drive to another friend's house in the British countryside and plug an almost-empty Tesla into the ordinary socket in the garage. After a weekend hiking etc, with little use of the car, it is full or close enough. That's something he can rely on in the UK/Ireland (13A@240V=3120W), something he couldn't rely on in North America (15A@120V=1800W), and the rest of Europe is somewhere in-between. (Does a typical German house have higher-rated sockets in the garage?)