I agree with everyone else. I personally wouldnt care for a pre-patina but i can bet there are home cooks that would love it as they dont cut a lot... constantly.
I can go through 8 tenderloins in a day prepping its easy to get a patina started... I also got enough knives that if a knife needs a bit more patina before it can really be a workhorse I can easily set a knife aside until I have more time to properly care for it.
most people dont own a $400 plus knife much less have many to choose from unless you are talking to a knifenut. I can easily someone deciding to invest in one high quality knife and wanting to use it right away with no muss no fuss and pre-patina would be the perfect option.