The post-doc agrees. They do the study, use some resources from the HotShot's lab and also run some analyses there. At no point in the scientific process is HotShot involved. The paper gets written and post-doc shows it to HotShot. Put me as senior author.
HotShots can also get a bad deal.
He has never seen the paper prior to publication, has not reviewed the data, and is dismayed at being included on this paper in this manner. A young scientist has a new facility, doesn't matter what exactly, could be the latest and greatest environmental chamber, nitric oxide analyzer, strength tester. Perhaps it's the latest molecular biology technique to analyze the speed gene. She knows her mentor had his name on hundreds of papers simply because he ran the lab. These examples illustrate the complexity of publishing scientific articles.