Yes; sites don't want you to know about RSS because it's a way to bypass their portals to just get to the goods.
I suspect that most sites that have RSS feeds don't expose them intentionally. They just used some framework which automatically creates it. If they knew, they'd put an end to it. "What, someone can grab a list of our items without seeing the main page at all? Turn that shit off!"
Even though the items do contain links that beckon the user to that site, it still minimizes their interaction.
No, it helps discover-ability, and makes me more likely to come back when instead I might not bother. Marketers and someone wanting people to read their content would know the value of RSS.
Even if you're ad-supported, I'm more likely to visit you if you have an RSS feed. Not to mention any non-profit or academic website could let people follow new developments easier.
I suspect that most sites that have RSS feeds don't expose them intentionally. They just used some framework which automatically creates it. If they knew, they'd put an end to it. "What, someone can grab a list of our items without seeing the main page at all? Turn that shit off!"
Even though the items do contain links that beckon the user to that site, it still minimizes their interaction.