There's a lot of consumers (millions of them) who try and make ethical choices. They obviously need information to inform them. If this wasn't the case, you wouldn't see the billions spent by coprporations trying to present themselves as ethical traders. I think it's dangerous ground to dismiss them as being stupid and therefore deserving of what they get (being misled). The question to my mind is more a case of where the boundary lies
Dustin Johnson has made no secret of his religious convictions, and indeed traded off them. If you're a christian minded golfer and decided to buy something endorsed by Dustin ahead of something endorsed by Tiger because you approved of Dustin's lifestyle and not Tigers, are you quite so sure that this person doesn't deserve a bit of protection and to at least be informed that Dustin ain't what he presents himself as, and under the circumstances perhaps you'd rather buy Bubba?
I think it's a slippery slope to say that "dumb" people don't deserve protection and by extension, are fair game. I can think of certain industries where deceitful selling and misrepresentation is endemic (financial servcies). Is everyone who has been sold a duff product 'dumb' too.
Health warning on tobacco products is another related area of course
If I can see a difference, it's that Dustin Johnson has said words to the effect of "I'm a Champion golfer and I use this equipment, it helps me play better golf".... that's clearly different to "I'm a good all round person of upstanding virtue, and I use this equipment, it helps me be an even better person"