Sheesh, isn't that what my Hubby did. By doing an MBA it opened up a whole new world. Of course it wouldn't be much use if you want to be an electrician, but if you want more than that, then, yes, it has been worth it.
If you are taking the average person, which clearly you are not as you are NOT the average sparky. Here are the facts of what the AVERAGE sparky earns.
http://www.workplace.gov.au/ims/NSW/Awards/12/01/92/support/AN120192_TOC_EX.htm
This is the current award. Pretty dismal if you ask me. Out of that line up, the best paid is the Electronics Tradesman @ $17.39 per hour. Now, you can earn more if you want to work all weekend AND there are plenty who pay above the award too, but you won't get many that pay double the award.
I will add that Hubby left school in year 10 to do his apprenticeship. He was VERY good at it & promoted to foreman at an early age. He earnt GOOD money for an electrician as every employer paid more than the award, but wanted better, so he did Uni as a mature age student & now earns more than double what he would have been earning as an electrical foreman, AND he only works 5 days per week.
He could have become a contractor, but decided that he would put his talent elsewhere. These days he is a project manager for a large corporate company. He travels around to different sites as well as spending time at the office. It is a job he is good at and one that he enjoys.