Ah, the old "the internet can solve information aggregation, for free, for all" case. From price search engines to review aggregators to services-searchers, the vision of the internet was that it would allow us to find anything, properly annotated and metadata-tagged, at no cost to anyone because information wants to be free. Easy to find the lowest price, from a vendor who has good reviews, for a product that appears to work and do what it promises, with some tips and tricks submitted by current users for a bonus... all just open and available. Those were the days... that never were.
Every price search engine, review aggregator and services-searcher (think Angie's List or other "find a trusted provider" orgs) since the 90s is either gone or just does affiliate links. So, even if you see multiple stores with links (Amazon AND Best Buy, 2 whole options!), it will only be to stores with a payback vig. Some of these sites will also use advertising to help pay the rent, and of course, eventually allow sponsored products to show up higher in the list.
I loved the idealism of the 90s, when we thought the mere presence of the internet would bring these things to life. It's too bad that the only way to make this stuff work is to basically sell out, if only a bit... and sometimes, the whole farm.
But is it always a sign that such a site or info provider can't be trusted? In some cases, sure. But note that Consumer Reports, one of the oldest and most trusted product recommendation orgs in the US (not trusted by all, of course, but by many) charges a subscription fee AND has affiliate links, and they still continue to survive with some sheen of quality (though, again, some think they are buffoons... I know this thanks to the Internet).