Items for sale here and on ebay without remotes....

To me a missing remote is mostly third hand stuff. Not the original owner. The point that it may mean the item was stolen? perhaps.The best way to avoid that chance is to buy stuff with the manual, the original box. I really think not to many burglars look for those things...

  I had a burglary in 1987. The burglars must have been in a hurry and didn't bother to take the time to take apart an entire rack of McIntosh separate components. They did steal the remote control for my McIntosh MCD 7000 compact disk player. I bought a new remote from Mac for $100. Burglars also stole my McIntosh XR-16 loudspeakers  (which I never did like). With the insurance money I bought a new pair of Apogee Duetta II loudspeakers, which still sound glorious to this day. 

Yes theft is likely very rare in these listings.  They break, folks lose them, 2nd or 3rd owner, Goodwill, etc......

I bought 6 used McIntosh pieces in the last 9 months and even though they came with the remotes, I ordered all new ones.  I get skived by using  used remotes.  I have seen people scratching their junk with the remote plus worse, why would I want to touch it?

Maybe a little off topic, but some gear (Cd players?) will lose a lot of their features without the remote. Many players have very stark front panels with only a few buttons on them.