Some things just don't make sense

[LSx_88_Ciera]

I was in the market for a new cordless drill since mine died.
During my browsing at local stores I found something that I found very perplexing.
Milwaukee 18V lithium-ion drill (2601-22) $199.99:
drill (2601-20), 2 batteries (48-11-1815), charger (48-59-1801) and case. $199.99
Milwaukee 18V lithium-ion impact (2650-21) $219.99:
impact (2650-20), 2 batteries (48-11-1815), charger (48-59-1801) and case
Milwaukee 18V lithium-ion drill/impact combo (2691-22) $199.98:
drill (2601-20), impact (2650-20), 2 batteries (48-11-1815), charger (48-59-1801) and case

Why in the world would anyone buy just the 2601-22 or 2650-21 when you can get both the drill and impact with a charger and 2 batteries for .01 or 20.01 less depending on which you were in the market for.
Heck you could get 2 combos, have an extra drill/impact/charger and 2 extra batteries for $20.02 less than the 2 if purchased separately.

After I went through the check out I told myself I was in the market for a cordless impact and they paid me $20.01 to take a drill.
I guess I must be a sucker for a good deal.

Just to cure my curiosity I checked other places online and it is the same most places I checked even Milwaukee's site.

I just don't get it any business/marketing people out there that have some insight as to why they would do something like this.
At first I thought maybe they are hoping you will buy more batteries since you have 2 tools but I could buy another charger and 2 more batteries and still be ahead vs buying separately. Although if I wanted more batteries I would just buy another combo since it is less than 2 batteries and a charger.