Marketing people aren't dumb. They just know that consumers are. "No blades you can stick your fingers in" is accurate, but buyers want catchy and memorable, even at the cost of slight factual inaccuracy.
Yep! You can blame marketers, but that's their job, and it works. Until society becomes a lot smarter and more cynical, people will be paid to make things popular, and they'll do a lot of really obnoxiously cheap things, and it'll all work.
Sure, a more accurate wording would have been "no blades that you can stick your fingers in", but you can't expect too much out of marketing people!