The idea Bloomberg is doing this to scrounge up discounts for ads against Trump is BS. The guy is worth $50b dollars. These discounts are chump change. He spent $225m running in his 3 NYC mayoral terms. He did the NYC mayoral thing for the same reason that Trump ran for president. Being a major politician wins you a lot more fame than being a rich guy ever will. Marcus Crassus was probably the richest Roman, ever. But if he hadn’t also been a Roman consul, no one would ever have heard of him.
You think President Trump ran for office to become more famous? That’s buffoonery.
Not necessarily only for the best price, but also guaranteed placement and frequency.
And not every billionaire likes spending more than they have to. Warren Buffet used to drive himself in an older Buick, just a few years ago.