Do it - the macro effect comes from the scores of people who only have an MBA. Adding a business degree to an engineering degree likely won't change your understanding of reality your grounded engineering view gives you.

I reckon there are better free ways to waste your time, and many don't require moral corruption.

Depends, do you think you can hold on to your humanity? Are you looking forward to working along side some of the most soul crushing people you will ever know? Really, it's nothing more than training you to view humans as nothing more than a commodity. If you are cool with either thinking that way or operating in an environment that demands that kind of thinking...