Obviously, I just made that up. But I gave the store the real one. Which I have since forgotten of course.
Since it’s a grocery store, I actually would expect them to check their trunk, since that would be the first lock I’d expect them to open. The fact they used the key at all suggests they use a key to open their trunk, rather than a separate fob. So the most natural place to look at would be at the trunk lock. Doubly so if it’s also an ignition key, since that suggests they took something out of their trunk after they arrived.
Now, if I was worried someone might do something with it, I could see moving the key, but I wouldn’t move it to the lock on the driver’s door. That wouldn’t really be any safer. Maybe I could see hiding it somewhere inside the car–but then you’d have to leave it unlocked, in case that’s the only key.
The obvious answer would be to take it inside and have them paged (without explicitly mentioning why, so people would think it was maybe that they left their lights on or something) and let them give the driver the key. I am not sure why they refused to do that.
Personally, I suspect I’d just wait and watch, rather than touch the key at all, hoping they arrive back. And then only mention the key if I see them looking and not finding it.
It was a very weak joke. 
But come to think of it, I honestly can’t remember the last time I heard a page in a store: “will the owner of a light blue Cimarron please come to the service counter.” That seems like literally 50 years ago. Do they still really do that?
Yes, they do.
Fords were big on that. Until about 25 years ago. What sort of vehicle do you have now with that obsolescent arrangement?
I stopped at a pet store to buy something and the guy ahead of me in line was paying for mature Koi he had spent a small fortune on, special order. He had 3 large boxes that took up his entire trunk.
He slammed the trunk closed, then realized he’d set the keys down inside the trunk. A small crowd gathered, offering advice on how to get the trunk opened.
I left, but asked at the pet store the next time I was there. The guy eventually called a locksmith, who arrived a few hours later. The fish were all dead due to heat. I asked if the store had a guarantee and the cashier told me it was a 7/7 guarantee. Seven minutes or seven feet from the door.
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LSLGuyhttps://boards.straightdope.com/u/lslguy Prolifically Prolix Charter Member
April 11
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Most, if not all, the cars I have had the ignition and trunk keys are different.
Fords were big on that. Until about 25 years ago. What sort of vehicle do you have now with that obsolescent arrangement?
Honda Fit
I’ve had a couple found phone incidents recently. One was a month or so ago-- was taking a walk in my neighborhood when I saw a phone on a patch of grass by the sidewalk. I briefly contemplated taking it and turning it in to the police station or something, but I decided the owner had a better chance of finding it by retracing their steps if I just left it where it lay.
Then just yesterday evening my wife and I were walking in a part of the neighborhood that doesn’t have sidewalks, so people walk right in the suburban street. I saw a phone in the middle of the street. Couldn’t just leave it to get run over, but fortunately a family out for a walk was about 100 yards ahead, and I yelled “anyone lose a phone?” It belonged to their teenage daughter. So, it’s kind of a case by case thing. In the OP’s case I likely would have left the key where it was.
Out of the 6 cars I own, all 6 have a different key for the ignition and trunk. Granted the newest car I own is 40 years old.
In my family, on our lockscreen images, we’ve added the text “if found call XXX-XXX-XXXX” where the number is for the other’s phone number. This way, a well-meaning finder can actually do something about it.
(Note, it’s easy to add text to an image using the iOS image app.)
Good idea. I didn’t think to check for anything like that in the first phone I found.
Found a phone on the side of a busy street - corners rough but not screen smashed (yet) as though it slipped off a car roof. Lock screen was a very dapper young man of about 8 in a sparky new red suit, but no other ID in evidence. I picked it up & took a picture of his picture and put it on my Facebook page - within moments a local barista replied ‘they were just here after church’ and knew one of the bigger folks he seemed to be with. Turned out they were fellow parishioners who happened to meet at the coffee shop…after about 2 more friends of friends I got to hand the phone back to his mom. Sometimes the stars DO align…
At least on Android you can add a screen crawl that appears while the phone is locked. That can include whatever words you want and be fairly long. An emergency contact to call if you and the phone are in an accident, who to call if the phone is lost, etc.
Back when I was working the most likely place for me to leave it was at work. So I also had my employer name and payroll number in there too so a fellow employee could locate me.
Mine has stopped working. If I long tap on the lock screen it appears, but disappears after the screen has gone dormant. I can’t even find where the setting that has my text is anymore.
On my Android Samsung it’s under Settings >> Lock Screen then scroll way down to “Contact information”. Since you didn’t say what kind of phone you have I have no idea if that info is helpful or irrelevant. But it might help somebody.
Samsung s20. I’ll take a look. Thanks!
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On mine it’s Settings->Lock screen->Edit, which shows my message scrolling on my lock screen wallpaper, but it doesn’t appear on my actual lock screen. I’ll fiddle with it some more.
Sounds like you’re getting warmer. 
Yaay!
If you have auto-unlock with your face, or at home or near your headset, etc. you can get in a situation where you never see the lock screen. It’s so eager to wake up for you.
Nah, I have a fantasy about my face and screen unlock that’s kinda like cutting off someone’s finger for a fingerprint lock.
You should spend less time tending to Hannibal Lector type people. Dealing with them triggers … unhealthy … worries.
Decades ago, most cars’ headlights didn’t automatically shut off. When I came upon a car with the headlights apparently left on, I’d generally try the driver’s door and – if possible – shut off the lights*.
For about a dozen reasons … not anymore. I’d just feel badly for the person whose battery might have died for a moment’s inattention, but … nope.
But you’re in Canada. The likelihood of you getting shot for what you did is infinitesimally smaller than it is for those of us in the US
*It was my observation that the silly folk who left their lights on tended to be assiduous about locking their doors.