I don't think you were wrong in letting the service director know about your experience..that's the purpose of those surveys and most BMW dealerships take those surveys seriously.
I recently completed a survey and it asked me if I got a free complementary car wash. I didn't think much of the question and answered it honestly in saying, "No." I usually like to limit car washing to myself so this didn't bother me. Within a day, my SA emailed me apologizing about the car wash and asking me to come in anytime for a free detail. I declined his offer since it wasn't a big deal, but it obviously was to them and it does reflect their rating to BMW USA.