We had our stroller stolen at
DisneyLand the last time we went. Actually it appeared someone had "exchanged" their broken stroller for our new one.
At first we thought someone had allowed their child to stand in the seat and broken/collapsed/ripped the seat, but as we inspected it more we realised it wasn't ours at all. Although ours was only a couple weeks old, I had already lost the snap-on latch that keeps the stroller folded, & the one left in place of ours had the latch, it also had white intead of navy blue tires and adhesive residue where a sticker had been removed. So we were pretty sure that it wasn't just a case of mistaken identity.
We told a CM and they gave us a voucher for a free rental, and they notified security and we went to L&F and filled out the paperwork just in case someone "borrowed" it for the day and had an attack of conscience and left it behind on the way out. (L&F CM said that they find literally DOZENS of strollers abandoned every night -- people's personal strollers, NOT the rentals!!) Most are never claimed; sometimes parents call saying they forgot it when they left.
I'm not sure how you "forget" your stroller... but one hopes they remembered the child that went with it
We checked back a couple times over the next week, but it was never found.
Luckily it wasn't an expensive stroller. I was more upset by the violated feeling I had -- that someone would have the nerve to do that. What were they thinking? They had to know we would notice.
Anyway ... we got the rental, went about our day, and tried to push out the negative thoughts about whoever took it by telling ourselves that they must have been in a pretty desperate situation to do something like that and we try to help those in need anyway, so .... But still, everytime we passed a group of parked strollers, I just had to scan through and try to recognize ours. I couldn't just forget it, so it did distract us for the rest of the day.
I like the idea of attaching something to the stroller to make it uniquely yours. (Ours was probably an easy take just because it was so non-descript. Just a lonely stroller sitting all alone) Those flags they have for bikes & bike trailers come to mind (I want one for my powerchair too) Or maybe one of those cutsie license plates, etc.
I have heard of someone who put a disposable diaper that was not used, but was folded as if it were, in the seat, or in a bag hanging from the handle (can't remember now) to discourage others from wanting to abscond with her stroller.
I guess that might work, but you'd sure get some weird looks I bet!!