I would trap the drone and then knock it out via a baseball bat or golf club or hammer. Then, I would take it apart and then find the factory reset switch. I would power it back up after I can confirm I have disabled it's antenna so it can't call home. Then, I would try to root it so I could make it mine.
This could be either 1.) I would look for a serial port or some other interface port where I could hook it up to a PC or at least get it a keyboard and monitor....
or 2.) I would disassemble it trying to find the storage device (hard drive, SSD, whatever), and I would then attach it to a PC as a secondary drive, once I am able to access the drive I'd copy the password file, and then try to break it so I could hack the root password.
Then, once I have control over the drone, I would fly it back to the pizza place, and then I would have it spin around in circles around the pizza place just going and going and going until it's batteries or fuel cell or whatever is low. Then, It would land on the roof of the tallest building near the pizza place in an awkward place.
I would videotape the reaction of the pizza man as his drone disobeys him.