Really? That seems odd to me. You'd think they'd still kick at least a little. Eh, I like drones and vehicles having to worry about it so I'll keep making them deal with recoil.
Weapon mounts on a vehicle ignore recoil, but, as has been stated, an optional rule exists saying drones/vehicles absorb recoil using their Body as an amount of recoil compensation. I use this rule too, as it prevents someone from mounting a super-machinegun onto a cat sized drone (body of 1 or 2) and going to town.
Since a typical car has a body of 10+, this generally means you can ignore recoil when firing from a vehicle. Smaller drones, however, need to keep track of it and so their rigger's should be aware of the issue.