Most free web sites pay for their upkeep with ads. It has been an unwritten agreement since forever (or at least as long as there have been ads on the web) that if you consume the content, you pay the creator by looking at the ads on their site.
Consuming the content without looking at the ads is like shoplifting because you don’t like the way a store’s checkout counter works and/or the fact that they want money from you at all.
Counterpoint: The checkout counter at the store doesn’t follow me out into the parking lot, grab my license place number and sell it to whoever wants it, or follow me into other stores.
Definitely an unpopular opinion, though! Take my upvote.