I think you read only the first & maybe the 2nd ad which had $85 & $60, respectively Kurt, & then formed a generalizing conclusion & submitted your post.
These are the last two ads on that page one of the Google hitlist:
GENUINE OSX 10.6 SNOW LEOPARD INSTALL DISC SCRATCH ...
boise.craigslist.org › for sale / wanted › computers - by dealer
Date: 2012-09-30, 6:29PM MDT Reply to this post. Reply to: ...
OSX 10.6.7 Install disc for APPLE that has no scratches. Asking only $20. 208-965-3676 ...
-* APPLE OSX 10.6 SNOW LEOPARD *-*
newyork.craigslist.org › brooklyn › for sale / wanted › items wanted
Date: 2012-10-04, 8:49AM EDT Reply to this post ...
UP FOR GRABS IS MAC OSX SNOW LEOPARD 10.6 FULL INSTALLATION FOR $35. THIS CAN ONLY BE ...
$20 bucks & $35 bucks, respectively.
Plus, the seller might be right down the street.
It's just an option. It's not cut & dried across the board that ALL Craigs SL disks are above $50 bucks. (Of course).
And again, might be right down the street.....
Think Different, Kurt. 😉
KK