Maybe if you try it for a living the reality of the situation might present itself more clearly. Optimism is always a positive thing (the half-full scenario) but optimism can only go so far before reality hits. However, I agree that as a translator it's not worth settling for the same price as a teacher when the job is a lot more specialist. You should be able to earn more (although I know one teacher who pulls in nearly 700,000 per month!!!)
Actually surprisingly enough, I know one company who uses an hourly rate, and it's great! The woman who I have dealt with, grossly overestimates the time taken per page, and agrees a time based fee in advance. I did a job for them before where I was paid based on their estimate of 14 hours, and the actual job took me less than 3!
However this is an exception. The per page rate is normally much better.