Marketing yes or no?

everybody talk about today's, Marketing is good or bad? do you trust advertising or not? you prefer advertiser consult about some product or service ,or some of your family member or your friends advise? if you ask such a question like that, majority of people reply you they dont trust Marketer.!!!
why? then why we studying marketing, and such a subjuct like CB,MR, and so on.
if our future consumer could not trust our advise!
i agree nowaday all the advertising is not totally trustable, but we should accept for attracting the consumers they should put some sign and attractive things.
then better we little bit change our mind against Marketing people