On I-10 in Mississippi, the cops knew it was a pipeline for illegal cargo, both human and contraband. They also knew that an unmarked truck as ooposed to a major carrier line was the most likely candidates. They customarily stopped those and sniffed them with their dog, always would see that going on side of road. But then, it did not take near that long to get the dog there.
DAWGS, your example is a perfect case of deciding how much inconvenience am I willing to endure in order to prove my point. And for the cop, how much am I willing to inconvenience someone to prove his point. And the poor dog was just excited to get out of the car for a bit and sniff around, maybe pee on your tire.