Basically, the field of consumer psychology is focused on the attempt to understand why people buy or use certain products or services, or how to persuade them to buy or use more.
It's not necessarily evil: the products or services are not always commercial - the health authorities trying to promote breast feeding or organ donation, or an organization offering free financial counseling can also want to understand their consumers. Of course many projects are commercial: checking how effective advertisement campaigns are, how a new product might change the perceptions about an old company, why some people avoid using certain products or how consumers’ preferences change over time.
The company I work for is conducting studies on all of these topics. Basically, what we study is motivations and obstruction and how they shape behavior.
The methods we use to investigate these issues differ according to the question asked, but are mostly taken from social psychology and cognitive psychology research: straight-forward questionnaires, reaction time measurements, semantic fields, affective reactions and so on. Most of our studies are run over the internet – a link with the experiment or questionnaire is sent to a large group of people (hopefully- a representative sample of the society in Israel). The work process is somewhat similar to psychology studies in the university; a question is raised (usually by our clients), an experiment is planned and run, data is analyzed and conclusions are made. The next step is a bit easier than in the academic world: instead of struggling to publish your work, we send it to the person who ordered it, and it's his/her job to figure out what to do with it.
For me, it was very surprising to find out that this field exists. I never knew the kind of experiments I used as a student are also used in “the real world”. I never knew there are people outside the university using SPSS. Now, when I’m aware of this field, it seems like a very good use of my skills and experience.