That's not a logical decision at all. Your claiming it is - does rather prove you still don't understand what "logical" means. 
Logic is not a synonymn for 'self interest' -indeed there is no logical answer to the question "which field should I base my career on" ? Nope "whichever pays most" is not a logical answer except to the question "how do I make most money".
It is just as logical to make the decision to become a philosopher on the basis that one may enjoy the job more, or a writer (english lit) on the basis that one would rather write stories than software.
All three choices are equally 'logical' until and unless one defines further requirements - what goals are you hoping to achieve ? Maximising income ? Maximising happiness ? The best balance between both ? 
Only once you have established criteria can logic guide an answer. It's extremely Randian (aka dumb) to assume "most money" is the only criteria worth considering.