I Walk The Wall

Why is it that given the choice between walking on a regular footpath and walking on a small wall next to the path, do I always choose the wall?

I walk this footpath every day, and when there's no one else in sight, I walk the wall. I must know its not a particularly 'adult' or acceptable thing to do, or I wouldn't hide it!

In my head, I'd always assumed everyone did it - but I've never seen it. Are they all hiding their secret wall walking too? Or is it just me?