I suppose you are opposed to beta testing software, because that puts the bugs in front of the unwashed masses rather than an elite group of programmers?
Of course the people filling out the survey are not the competent designers. They represent the target market for the logo, the end users. The people looking at the feedback from the survey are the competent designers. They appreciate the feedback and the comments they received from users in our target market. It is one source of information that feeds into the process, but not the only one.
Of course your analogy is flawed since we're not asking your "monkeys" or (whatever you want to compare open source users to today) to design a logo, or write play. We're only looking for feedback from the very group of people to whom the logo is targeted. Think of it as feedback and part of iterative design. Those familiar with User Centered Design would understand this best. But the concept is not difficult.