Make sure you post them in the template and not every post (as some pages might go over the limit of ad units..)
So true, in the end it's us who publish their ads so they can make bilions each year. I love AdSense for blogs and I'm sure we all like to see the money coming in.
if the content of the blog is not against the adsense tos, you are allowed to use adsense codes on blogger.com blogs
It's the easiest way to get approved for adsense. Once you are approved for your blogger blog, you then use that account for any other site you have that applies to guidelines. The widgets that you use in the layout section specifically support adsense.