Happy New Year. Straight into it after a long lay-off...
It is not so much the financial maths that is the main limiting factor it is more a question of relinquishing control. The marketing department in yer standard corporate monolith is not going to give the control of their brand away. It is a question of ownership. They own it and they will continue to want to own it, no matter how much they talk about the brand being a representation of employees blah, blah etc.
A related point is that corporate culture depends on bean counting. That's why broadcast media is tailor-made for these types of companies. You punt your message out through three or four kinds of channels and then measure the results. With micromarketing you can measure results but you can't assign an increase or decrease to a particular action or set of actions. That makes 'em nervous. If you can't measure it, it doesn't exist. As a corollory - if you can't measure it, you don't exist.
That is not to say however, that the results of Gonzo Marketing can't be measured. But imagine this scenario: you are presenting the latest sales results to the VP of Worldwide Widget Sales (which incidentally are going very welll because you have started talking to your customers instead of shouting at them). When all of a sudden he asks how you know it is your fine new marketing tool that has achieved such spanking sales.You pause, cough and point to your bursting in-tray. "Because my customers tell me so", you venture. Ah, but what about the focus groups, and all the other paraphrenalia? Don't have any? Goodbye.
In short they won't accept the measurements it produces. One thing these påeople don't like to be is nervous. GM is a loose cannon (as they would say) Don't know when it is going to go off.