Does anyone know what these were for?

That's a later 9600 motherboard--the Mach V--and those are solder points for the old L2 Cache which was moved to the daughtercard with the introduction of the Mach V.

The Mach V is the more desirable motherboard since the lack of an L2 Cache makes it easy to use a G3 or G4 upgrade daughter card and utilize their larger, faster caches. If you want to upgrade to a better daughter card, and you've got an older 9600 motherboard with the cache soldered to the motherboard, then you can disable that old motherboard cache--and thus enable the upgrade cache--using these steps:
http://www.geocities.com/pm9600g4/l2cache.html

There's no cache slot on those boards?

Nope, no cache slot. Rather poor planning by Apple, yes? (Or maybe like the G4 block in the B&W G3 firmware, intentional near-future obsolescence?)
There's only a ROM slot on the 9600, for which Apple never made any upgrade cards. The original ROM too is soldered to the motherboard. The Mach V also had the ROM soldered to the motherboard.

Here's a simple layout and description of the first generation ("Tsunami") 9600 motherboard:
http://www.macgurus.com/products/motherboards/mbppc9600.php