Whether you know it or not, you are making a good argument for a self-selecting poll.
How many times have you told your friends about that great meal you had at that new restaurant you discovered yesterday? Now, how many times have you told your friends about the great meal you had at McDonald's yesterday?
The clearly superior but less well-known In-n-Out fries are likely to motivate people to vote in a voluntary poll. McDonalds may have pretty good food and it is safe (you're less likely to get sick from a McDonalds than some unknown fast food dive). But it won't motivate voters unless it is exceptional food.
The bottom line is this: When In-n-Out wins, people who don't know much about those fries will find out about them, and In-n-Out will get the notoriety it deserves.
On the other hand, if you call around town and get McDonalds as an answer, it is neither a surprise nor is the information of any real use since all the product wins is a brand recognition contest. A large random sampling will always yield more votes for the best known satisfactory product, not the lesser known exceptional one (yes, everyone knows about OS/2, Linux, BSD, Solaris, etc, but far fewer people have "tasted" them).
I don't usually like analogies, but this was an instructive one (thanks go to the person who originated this thread).
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