There are also modified commercial drones that just drop explosives, and that is what is mentioned here. Those drones drop their payload and may return to reload if not shutdown. Those drones aren't "hundreds of thousands each", but around $500 each.
As for the drone you linked - we don't know how much it cost Russian to produce Geran-2, but definitely less than you imagine.
Even this is almost certainly an underestimate. Open source intelligence that just the bill of materials for a Shahed is more than the tens of thousands previously estimated. These are probably more on the order of ~$400k [0]
This comment thread is about cheap drones hunting down individuals. They are not using Shahed for that. You can easily build a small drone capable of carrying a grenade for under $300.
https://en.wikipedia.org/wiki/HESA_Shahed_136