Why hasnt a turntable manufacturer produced a table with automatic tonearm return/shutoff?

Personally, I prefer to have as few things in my turntable that can vibrate and adversely affect the sound - I also remove the dust cover when playing records -  plus, if it was a big deal for me to have automatic turnoff and return, I'd listen to CD's or stream instead. 

But I remember the old spindle stacker days when I was a teenager. I also often didn't bother putting records back in their covers back then! 

A lot of audiophiles assume something like you describe would add noise to the system (while have no evidence) but are happy to have monoblocks and all the connections that go with them. Go figure.

Concept 2QD is a really solid table and does just what you speak of…😎

@roadcykler 

monoblocks and all the connections that go with them. Go figure.

You mean that pesky additional power cable? 

@kavakat1, several features have changed/evolved(!) over the years.

Tone controls were common into the '70s but became rare after that, except on receivers which were more of a consumer product rather than audio hobbyist.

Speakers once commonly had bass and/or treble switches to adjust other than flat.

And yes, into the '70s automatic turntables (start up and shut off) were common.

But about that time reviewers (led by J Gordon Holt, then Harry Pearson) became more critical of component performance and recommended those with fewer features which were considered detrimental to "pure sonics".  Manufacturers of higher quality components followed this criticism.

This is not to say all hobbyists wanted to eliminate these features.  Some continue to call for their return, you included.