Why a 12V battery in a 18V kit?

The pic below shows a combo kit available in Australia. Just wondering the the M12 battery can be used by the driver or drill here, or it’s assuming you have other Milwaukee 12V tools already?


[External image (assets1.gettoolsdirect.com.au), not copied]

Ended up buying the kit today and it became obvious why the 12V battery was given, as

a little book showing all the 12V tools was also inside (but nothing showing the 18V range).

Gateway drug.

 

After performing a quick search I found the link to the seller: https://www.gettoolsdirect.com.au/milwaukee-gen-ii-18v-2-piece-5ah-combo-m18fpp2a2-502c.html.

This could be viewed in two ways: as the “gateway drug” into the M12 system mentioned above, or as a way to intice current M12 owners to buy this M18 kit.  I think both theories have merit.  Already own a number of M12 tools but thinking about getting something with a little more power?  Buy this kit and get a spare battery for your existing tools.  Need this particular tool kit?  Buy it and find yourself tempted to find something to use with that free battery (I didn’t see any other versions of this kit, unlike in the US where we often have a choice of bare tool or battery).

To be honest, this line of thinking got into DeWalt.  I picked up a bunch of 12v Max batteries on clearance for $6-$12 each, then found a Bluetooth speaker on clearance.  A few months later I bought a clearance 20v Max kit due to the cross-compatability of the batteries with the speaker and charger.  🙃