I'm not so keen on the marketing fluff either, but there are definitely needs being met. The cases I'm most familiar with are in psychological research, which consists of having people fill in a lot of questionnaires (asking about mood, stress-levels, or testing cognitive skills). Qualtrics provides a service to easily build these questionnaires, send them out to respondents, and collect their response (and export the data for later analysis in packages like SPSS). With a little bit of extra work, you can even do highly interactive tasks like Stroop through Qualtrics. For the average psychologist this would simply be undoable without this type of software.
Similarly, class-action lawsuits often require sign-in through filling in some sort of questionnaire. Previously, these questionnaires would be handled through live phone interview, which is obviously very intensive for both the interviewee and interviewer. The questionnaires are often quite interactive, with different questions being asked dependent on answers to previous questions, or aggregates of previous questions. It would take skilled interviewers a while to learn to interview for any one questionnaire. Qualtrics (and similar survey software) makes this process much, much simpler.
You then also have your regular marketing research, the value of which can be debated... but it is obvious people are willing to pay for the creation and distribution of such questionnaires.
Beyond this, I'm sure there are a bunch of other applications of the software.