Today, at the supermarket, a salesperson who had set up a booth was trying to sell me some detergent. I ignored him at first, but then he tried to emphasize that this was not regular detergent. It had their special "Power of Vibrating Molecules" technology.
Wait... WHAT? I asked him to repeat. He seemed pleased at my incredulity, and went on to repeat it.

Quick tangent: You know you've had too much internet when the first thing you think of when you see a public slip up is: "I should blog about this!".

I'm not going to waste characters trying to explain why this is wrong. Just, no. — I'm not going to waste characters trying to explain why this is wrong.
Just, no.

What I want to know, is why advertisers, marketers and designers can get away with this at all?

There are, as far as I can think, two possible scenarios that could have taken place.

The people ivolved didn't know middle school science, which everyone is supposed to have given exams on.
There's not much I can say about this except they are probably not competent enough to do their job. I'm not asking everybody working at detergent factory to know the entire chemistry behind hydrophobicity, but they at least the people in charge of putting words on the label should know enough science not to humiliate themselves and the rest of the company.

You may think this eventuality is bad, but the next one is even worse.
The people involved knew the basic science behind this, but didn't think it would be a problem because the target audience was not sufficiently educated to know the truth.
This basically means that the people who study their target audience for a living have come to the conclusion that said audience is so woefully ignorant of science that they could write just about anything they pleased and people would lap it up, and still buy their product.

If this isn't proof of concept that the general population is in urgent need of a little science education, I don't know what is.