You'll see things like that on a lot of sites. Like many free sites on the internet, I imagine Fiberglass
RV needs to use ads to help pay the bills.
Those type of links are ads. You'll just need to learn how to tell them apart from the rest of the links on sites and only click on ads you're interested in. You can tell this type is an ad by the small "piece of pie" shaped icon next to the x in the upper right corner. I just took a look at a couple and they were for email programs/apps (My Inbox Helper and My Email Center were two of the ads) but they could be ads for anything.
Websites sign up for ad services and usually have very little control over which individual ads display.
It's just the way this part of the internet works.