You need to check your oil more frequently. The car could have simply used 1.5 qts in 7000 miles - that would be far from extreme usage, which is more of the 1 qt per 1000 miles.
Changing the oil on these cars is no harder than any car. In fact, I'd say easier, as the oil filter isn't going to drip all over the frame or suspension like many American cars I've had. Resetting the OBC's counter is easy too.