Some zones are event wastelands. Other zones have them all over the place. If you're in a same-level zone and there are no events going on (Snowden Drifts, Gendarren Fields) then you aren't going to be earning much XP. If you can go to a previous zone full of events you'll earn more XP due to more events.
Maybe when all the bugs are fixed and they tune event triggers better so that there's always something to do it'll be easier to say "just stick with level-appropriate zones." Until then, go where the action is.
The action is most certainly not in Snowden Drifts. I hate that zone.