Waste of time is in the eye of the beholder. It is a hobby, then maybe not a waste of time, but something contrived isn’t really representative of what I’d call an open opportunity for learning and enjoyment.
Producers love them because of the attention grabbing potential coupled with dozens of ‘hanger moments” that keep the viewer on station throughout the interminable commercials.
And because there's no cast to pay ...
“Producers love them because”
...they’re damn near free to make, and sell insane levels of advertising.
Ya know, The Bachelor could schedule a date in space and still make a huge profit.