I was filling out one of those online satisfaction surveys, and in the introduction, it reassured me that

This survey is anonymous.

The first question on the survey:

Enter the support request (SR) number below.

Yeah, because they'll never be able to trace the support request number back to me.

(I suspect that the reason for this contradiction is that the organization that wanted to conduct the survey used a site that supports either anonymous surveys or tracked surveys, and they opted for the anonymous survey for whatever reason—maybe it's cheaper?—but they actually wanted a tracked survey, so they made the tracking number part of the survey itself.)