"According to Google, millions of people every month stumble upon pages with insufficient mobile subscription information and wind up accidentally signed up for premium texting services and other unwanted plans. Instead of allowing sites to essentially trick people into getting charged for a service they aren't even aware they signed up for, Google is implementing new best practices that will make clear some of the details that websites try to hide."
Millions every month is a big number. I have not run into one of these sites, and I'm not sure what the tricks are, but if one wants oneself and others to be safe, sharing your data with the Goggle police about these sites seems to be a fair tradeoff for safety.