This isn't an insane move. It's a calculated, rational, plan to keep on escalating to split NATO apart. If successful, Russia will demonstrate that Russia can attack NATO countries without actually triggering a real response, paving the way to actual ground invasions.

Russia wants Estonia, Latvia, Lithuania, Finland, etc. Unless we respond with force to attacks like this, Russia will eventually win.

Secondly, all these drone attacks are collecting intelligence. These drones are not one-way deals. They all have satellite and/or cellphone communications (e.g. with SIM cards) back to Russia, allowing Russia to collect intelligence with each flight.