Howard got his payday the first contract; this second contract he obviously took a massive pay cut. This is evident for a number of reasons, including his decision to sue them for more money AFTER he re-signed, as well as his ongoing badmouthing of the company. I have long argued that Sirius understands that Stern's show is of marginal value to the company; what matters most to them at this point is being able to use his name in marketing and also having him signed exclusively nearly ensures that whenever he makes news or is on TV, Sirius also gets a mention. Basically, Stern is trading on his name and reputation...the issue of producing a good radio show barely enters into the equation.
As to advertisers...what is left of Stern's audience is not very attractive to them. Older white men are generally speaking not your primo demographic. But that demo does lend itself to bullshit advertisers who want to cheat on their wives, pay for sex/dates with women ("name your price"), need identity guard, etc. Back when he had the E! Show his male audience was younger, hence the Girls Gone Wild ads which were popular with guys in their 20s.
With barely any audience left, no major company is going to risk hooking their cart to his wagon as it might cause a lot of controversy. Back when he had millions tuning in, folks like Heineken and Budweiser could take a calculated risk because they were guaranteed shit-tons of ears listening to the ads; now....not so much.
Contrast the current version of THSS with a popular podcast like This Week in Tech (TWiT). TWiT receives millions of downloads each week and routinely has thousands of people in their chat rooms while the host is on air. TWiT fairly consistently has Ford Motors as a sponsor as well as Amazon (Audible). When Ford Motors buys a live-read for TWiT, they know almost exactly how many people will hear their ad (downloads are tracked), and they know the audience demographic pretty damn closely (men who love tech) so they do ads about how Ford cars contain Ford Sync and other neat tech. Now would Ford Motors buy ads on THSS? Fuck no. Ratings aren't given out and they probably only have Wiggy's claims. And think about what would happen if somebody started shouting NIGGER during a live read? It's a boycott just waiting to happen. Who needs that fucking headache?