If your smart phone (Droid and Apple) is in a default state it is fully archived to the iCloud/NSA. Find another handset wipe it and enter your username and password, 95% recovered in five mins.
You wouldn't need to wipe it - just install the Tesla app... you'd be on your way in minutes - you could even drive home and get the key card. Have I ever lost my phone? Nope. As you say, the phone is backed up in the cloud, a 5 minute job to get back on a different phone. The car can also be driven (and payments made) via a smart watch too. I guess you could lose that too... naked on the side of a motorway... at night. It could happen.
Technology such as this, electric seats, electric mirrors, contactless payment etc is never going to appeal to certain types - I can imagine similar protests when the internal combustion engine was first introduced and threatened horse-drawn carriages. Most have never owned or driven such a car, as a consequence opinions are rather uninformed.
