Wiper Fluid Reservoir Red Rocket Surprise!

I was cleaning up under the hood today, and a reddish color in the neck of my wiper fluid reservoir caught my eye.



Knowing this should appear blue, I was quite curious ... so I popped open the cap, and this thing rose up to greet me!!




I pulled it out; it's like foam pool noodle material.



I have no idea what it is or why it's in there, but I have a theory:


I don't use the wiper fluid, because my CF hood didn't have cutouts for the nozzles. I keep the windshield heavily Rain-X'd anyway, and with the frequent rain here in Florida, the windshield generally stays fairly clean. As such, I never refilled the reservoir ever since changing the hood a few years back. Interestingly, the reservoir is completely full now -- not by my doing.

So, my theory is: one of the times it was in for service (e.g. free oil change at the dealership, recent R&R of crankshaft position sensor, etc.), perhaps it was being inspected, and they noticed the fluid was low. Perhaps they go and check all the fluids first, and then go refill what needs it -- so perhaps they use these foam markers (it was red, after all -- red for bad, low, whatever) and stick them in the fluid ports that need a top-off. And, perhaps this time, they absent-mindedly closed the foam marker in the neck of the reservoir, or perhaps it was so low it fell way down in there and they couldn't get it out at first -- but driving it since then has shaken it loose. Just a theory anyway ... all I can say is, I certainly didn't put it there!

Anyone else have any thoughts?