I’m on your side against atomicblocks, but in my 65+ years of speaking English I have been in many, many situations where “a couple” of things meant exactly two. Even situations where the exact number is quite important but also familiar and understood, like “take a couple of aspirin” or “I hitched a couple of horses to the wagon.” But also many situations where it meant a small handful or the exact number wasn’t important. Both uses are acceptable but “a few” or “some” or “several” are preferable if it’s three or more. People who ask for “a couple” while expecting more are pretending to themselves and you that they aren’t being greedy.

The person you called a pedant is merely literal-minded.

It’s the phrase “a couple of blocks” that was under discussion. And then “ask me for a couple of something and I give them exactly two.” Couples of people didn’t arise until you shoehorned them in.

Those few blocks may be constructed in such a way that they’d be walking in the road with traffic whizzing around them. If there ever was a sidewalk it’s been removed to add another lane for cars.