Unfortunately a similar situation happened to me the first time I went to a gaming club when I was first getting back into the hobby, whereby I chose to play the only guy who was free (first sign) and he was sat with about 5 hobby cases with him. Needless to say I got caned in gaming terms (twice) but he wasn't actually a complete dick about it, he was pointing things out to me. Admittedly, looking back, he wasn't playing an 'uber list' considering it was grey knights, but there was no way I was anywhere near capable of beating him back then. He just played quite well tactically when I was still getting to grips with 5ed. I feel that in the long term that situation has actually helped my game because I know what I never want to turn into and I made a massive point of memorising the rules afterwards.
Yes, it isn't a situation I would like to go through again or inflict on someone else, but actually it spurred me on to improve tactically and not turn super competitive. However, it is part of my character to come out of situations and experiences like that and taking things on board and using that to push forward. However yes there are lots of people where that could easily have put the off the hobby and the club..
Perhaps instead of a questionnaire there should be an audition game to join the club?