What you really will be learning is the domain and the different problems people in those industries face and the solutions that are acceptable to them. We as developers/architects should and do become domain experts in solving certain types of problems.
Say, by chance you learn how marketing affects business decisions - you'll gain a better understanding and foresight into what is expected of you (always to drive up profits!). If you do decide to leave for another industry - marketing is still applicable there. Perhaps then you will be on another boat - building the things marketing promised - or where you will be tasked to build a home page where knowledge regarding conversion, marketing copies, pricing structure and analysis (ex. A/B testing) will make you an asset to the business.
I'd say give it a try. I am interested in working for Microsoft at some stage (I focus primarily on .NET) - but after reading that they consider someone with 7 years working experience in development a 'beginner' i.t.o full-time employment - I reckon there's still a lot I need to learn till then.
I'd say if you're still interested in Silicon Valley by then, keep an eye out for job listings :).