If people were indifferent (50% chance of wanting facebook) then the likelihood of at least 27 out of 37 randomly asked people saying "no facebook" is about 1 i

If people were indifferent (50% chance of wanting facebook) then the likelihood of at least 27 out of 37 randomly asked people saying "no facebook" is about 1 in 300. And that's counting the "Yes but I hate it"s as yesses. Count those as "no" and it's 1 in 3000. Highly significant. This assumes the "random tourists in Pike's Place market" are an effectively random sample. It's possible that facebook fans are less likely to take vacations in Seattle, but Occam's razor is against it.