Advertising may be a separate company (though the manufacturer will surely have its own marketing department contracting and overseeing), but that's a detail, nothing more. The factors that drive the use of such techniques to drive sales are the cause, and whether they are done in-house or contracted-out doesn't matter.
You've now got me thinking about how advertising could exist without driving consumerism, but I suspect that it's not possible - it would end up like tobacco advertising: you start by restricting certain associations between product and lifestyle, but in the end it just has to go completely
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