Well its useful to the company just to get their name out there. If they can get 1 in 50 people watching tv to buy their product once, their work is successful.

As for advertising, I can see through it very very easy and I can spot the psycological ploys that they play. I think I am the only person in america to count words during a commercial whether it be 'pepsi' or 'easy' or 'fun'. If you pay attention, you will see how much commercials repeat a word 6-7 times in the span of 25 seconds.