No need for the nav bar

This story from eWeek covers the topic of blogs that "install programs that are widely considered to be spyware and adware onto visitors' computers".

The problem is associated with Blogger's navigation bar, optional for those who (like myself) use the Blogger tools but host our blogs outside of the Blogger network.

What I am wondering is why someone who has a blog, and uses it for commercial/business purpouses, wouldn't host it themselves - and thus eliminate the problem with the Blogger bar. And why would anyone want to display Blogger's nav bar if they didn't have to? I am sure there's a reason, but I just don't know what it might be.

I would under no circumstances recommend anyone to leave a business blog on a free hosted service, or indeed to display a navigation bar for the service. Why? There is no added value for your customers, and it doesn't help your business.