Why rechargeable batteries?

Why do the instructions say to load non-alkaline rechargeable AA batteries into Sparki? Does it charge them when the USB cable is plugged in? Would straight AA alkaline batteries work? Or would they damage something?

I’m not sure where it says that for Sparki? Either is fine. The USB cable does not charge them.

arcbotics.com/using-remote/ says it in instruction #2 under "Using the Remote"
Thanks for the reply - I can relax and not get into buying rechargables and a charger now.
Alkaline AA’s in bulk are cheap as dirt!