Even if we don't measure 1/60 exhpts, we STILL say you use 1 exhpt each 10 mins you are walking - multiplied with carrying extra weight etc, of course. This simply means you have to take some breaks during your marches, or ambushes will become even more dangerous.
As for sprinting and distance running - sure, they can be nice. And with a Mage with lofty bridge you can fast sprint without using any exhpts (OK, 1 pr ten mins) when you get high enough levels, and it also presents other options for "running away". However, in the situations where we have had to run away, horses have been used - and required. Usually, beasts and monsters will outrun you unless you're on horseback, even with a good running skill. The "standard" situation is when we've been attacked by packs of wolves. You know, when they are many, they can be quite dangerous, and I don't think you'll stand much of a chance running away from them unless you have a horse...