Okay NEWBIE question

Am I wrong in thinking that Internet Marketing is far more straight forward in it's approach that Search Engine Optimization? I know in SEO there are a million and one steps and things you must do from Links to Code to optimize a site.

But shouldn't internet marketing be fairly easy to report?

Spent This Many Billable hours doing this
Spent this Much Money via this Pay Per Click site...

I'm thinking that you should be able to get a monthly invoice from any service industry. Doctors, lawyers, pest control people et al can give a detailed list of services and time spent, so should an internet professional