Thanks for the thoughtful response! (I'll embolden for clarity - let me know if I didn't reply to a key point).
I think that marketing has a massive effect on what we choose to buy. We are essentially told what is favorable and what is not, through advertising. The commodities we consume become and their companies become almost alive in our human perception - Nike, Adidas, Nokia, Rolls Royce... they are all something that have come to be perceived as something which is part of the construct of social reality that we live in.
The point about the ability to follow what marketing suggests is an interesting one. I'm not sure that I can see the effects of a sort of prevention due to lack of funding. Those who lack funds, i.e. the poor, still want goods which more well off people have, and have similar perceptions of those goods. I see people with little money, and they have IPhones, and its crazy, but seems to be what happens. I assume people will find means to achieve this, like using credit, or shops like Bright House (massive interest rate on goods, but monthly extended payments).
The point I made about Christmas perhaps isn't the best example... maybe it is, I'm not sure. But Christmas has become a time of huge spending, as completely separate to other connotations that it used to have - in Paganism, then Christianity, and then it has sort of been taken over by capitalism (i.e. Coca Cola).
Both consumerism and goods, brands, and technology etc, sort of become culture and what we know as the world in which we live - and really take on a massive significance, I think, in a way akin to language.
The thing is with branding, like you say, is not necessarily a bad thing. In a way, it can sort of augment our social relations etc. and make life I guess in a way, more vivid.
I do think that we are indeed brainwashed to a very high degree, which took me a psychology degree later to realise. We ultimately make our own decisions, but the variables and the importance of specific variables over others, and constraints of thought are in a way determined by external sources.
I'm not too sure what you mean in the last bit, with the sort of countermeasure as is the case with packaging.
I don't have references at the moment, and not a sociologist. Though I did write a psychology essay for university on the subject, and find it very interesting. There are some absolutely amazing books on how we are influenced, such as Thinking Fast and Slow, and another by... Cialdini on the methods of influence. Can't remember the name.
Something I'm interested in and would be happy to discuss!