This kind of thing goes back to the "community song" movement of the 20s, and there's no sensible alternative to singing off a sheet. There's a reason why the News Chronicle songbook sold as well as it did.
There is a sensible alternative its called practice and menorisation most of the ukelele stuff is fairly simple chords that can be learned quickly, it is just laziness

Twaddle. The community song movement never depended on memorization, and for what they were doing there was no earthly point. Nor is there for the ukulele groups. Their repertoire is far too big and fast-developing. I suspect you've never been to one.

The community-song thing was a mass movement made up of people who were very well practiced in singing from books - that's what every churchgoer does, and most people in community singing already sang hymns every week. There was then (and still is) a FAR larger proportion of the public who knew how to sing convincingly off a sheet than the total membership of the folk scene at its zenith. The sad thing is that folkies have accepted an abysmal level of incompetence at interpreting songs from print. In a church, that would get you edged towards the back of the room so most of the congregation didn't have to listen to you.