This is really not much of a change from 1976, when Gallup first started such surveys. Anyone in business, TV, journalism or advertising is perceived to be smarmy, while cops, firemen, teachers and nurses are well-received. Clearly, actually helping people during tragedies is more honorable than taking pictures or writing about it. This despite the fact that 52 journalists have been killed in 2013 gathering news for the rest of us.
I suspect that one of the enduring problems for journalists is that as some of them move from reporting and editing into video commentary, they begin to blend in with everyone from failed politicians to comedians who use the news as a jumping-off point for their opinions. Or journalists appear on shows where they don't get much face time unless they scream and yell or generally act like jerks. Otherwise the other jerks are featured because they drive ratings. And if we have learned anything this year, it is more about the likes, the links and the overnights than it is about the veracity of the news.
The Internet has redefined the public's notion of what a journalist is, with content heavily weighted toward opinion and pretty light on the who, what, where, when and how. Having a keyboard (or even outdated credentials) does not make you a journalist. Real journalists are often put in untenable situations having to interview those struck by tragedy or those who think their wealth and power should immunize them from close examination. They are not at home working in their pajamas.
I have worked with journalists for 35 years (and even been one from time to time), and I must say that while I have seen lots of lazy ones, I can count on the fingers of one hand those I would say had questionable "honesty and ethical standards."
Journalism is pretty much like every other profession. It has its earnest, diligent and honorable workers, and a small dose of those who kinda cut and paste it together -- and if all else fails, make up details and quotes. Even when practiced at the highest levels (where every effort is made to avoid sensationalism and just stick with the facts), journalism is imperfect. In spite of j-school and hard, on-the-job training, reporters’ and editors’ own personal biases and POVs can't help but leech into stories, if only in deciding which stories to cover and which to avoid. So it is incumbent on audiences to read the same story from a number of news organizations to get a well-rounded idea of what really happened. Few of us actually do that.
Most of my friends are in advertising. And they too do not suffer from low "honesty and ethical standards." They have to work on business they detest and at times crank out creative that makes you think they have either no soul or no adults governing their output. The same public that thinks ad men are unethical are the same ones who swear they totally ignore all commercials, but unconsciously reach for brands that somehow resonate with them. You say that advertising is creating subliminal desire for unnecessary products; I say that businesses have a right to promote their wares.
End Note: As we move into a season traditionally marked with hope and renewal (in addition to conspicuous consumption and excesses of all kinds), take a moment to consider that however imperfect our society, we are the luckiest nation on the planet -- journalists, ad men and all.