Keys are in-fact often left in this type of vehicle, but there’s no ignition and you can’t really drive off in them. That aside, I do see keys left in jetways at airports an awful lot:
Above, Midway Airport, Chicago. (December 2019)
Boston Logan, MA (BOS)
Charleston, SC (CHS)
And another, Midway Airport (MDW).
This is what I was asked when I shared this information before. “Is somebody going to drive off in a jetway?”
They’re right, there’s very little you can do here with this key (to my knowledge). But it does show a larger problem: These key switches were presumably implemented by the manufacturer to dissuade non-certified and trained operators from moving jetways, as well as the general public. Through training, the folks who move these apparatuses are clearly being taught to leave the key in and treat it as a manual switch instead (several airports I’ve been to, including O’Hare (ORD) actually don’t have keyswitches that I’ve seen).
The issue here is: Why is there a key here? It is failing at both jobs: Being secure and being easy to use. Furthermore, what impact would happen if somebody were to take a key? Financial to the airline or the airport? Punitive for the employee at the time?
I’ve mentioned this on Twitter to TSA, but did not hear back.