As a consumer of information, your time, attention, and even your action of clicking open a link is a valuable commodity. Websites glean money from advertisers based on the number of views, likes, clicks, etc. Both legitimate and hoax news sites have a stake in trying to get your attention, but reliable news outlets also have journalistic and editorial standards that (usually) keep them from resorting to click bait or outright emotional manipulation. Their primary purpose is to provide factual information to readers. Hoax news sites and many hyper-partisan news sites have fewer scruples. Often, these sites' primary purpose is to make money.
For a more detailed account of how fake news sites can make money off of us, here are articles from the LA Times and Washington Post that outline important connections between advertising and fake news:
Sites and content creators who don't care about accuracy or quality reporting will use clickbait headings, writing, and images to make you outraged, sympathetic, or angry. When online content provokes a strong emotional response, people are more likely to click and share it. This means more money for the websites promoting emotionally manipulative content.
When many media outlets and sites work to manipulate our emotions, we tend to become more entrenched in our views, less able to see other perspectives and viewpoints as valid, and more likely to dislike people who don't agree with us. In the United States, this contributes to political polarization.
When people see a lot of fake news, they may think all news is fake and that no news is reliable. This is far from the truth. Professional journalists have training and experience not only in things like interview techniques and fact-checking, but in ethics and things like libel law. Good journalists are human and subject to biases like the rest of us, but in their professional capacity they strive for objectivity.
Below is a link to the Code of Ethics for the Society for Professional Journalists. It outlines core journalistic principles and sets standards for reporting:
Individual newspapers and news organizations often publish their own standards and principles as well. Here are some examples:
Almost all news outlets (legitimate and fake) rely on advertising as a source of income. Professional journalists and editorial staff are paid to do quality work, including fact-checking, conducting meaningful and ethical interviews, and striving for objectivity. They work quickly, but it still takes time, effort, and money. When readers are drawn to "news" not to learn information but to confirm pre-existing beliefs or to feel the sensation of being outraged, fake news sites draw traffic from legitimate sites.