Earlier quoted context omitted.
if only most of the US labor force didn't rely on jobs in that sector...
If only manual laborers in 1850s England didn't rely on jobs that were replaced by machines (England went on to be far wealthier and provide far more opportunities to its people after the industrial revolution).
As far as I can see many of the jobs we do these days don't provide any real value. In this case cashier doesn't provide real value so good riddance. But I'm not confident we'll find ourselves in a better place in the future.
Also, somehow we undervalue manual labor with some skill and unions don't seem to work as well for non-factory/hospital/plant jobs.