Dateline: Madison

Okay, so I saw this sign today:



It took me a few hours before I realized that the sign probably meant that you were not supposed to go out and further plug the meter (in Minnesota we use the phrase "time limit" a little more directly). At least I hope that's what it really meant. The alternative is that it is genuinely stating the blindingly obvious.

Also, is the placement of the sticker random, or is it meant to transform the phrase from Vehicles may not remain in these stalls longer than the time limit of the meter into Vehicles may not remain in these stalls longer than the time limit of the me?

What is the time limit of the me, after all?