But the person I'm replying to didn't say "the price fixing mentioned in this article might also be applied to hotel prices". He/she said "Presumably because the CEO is mates with the competing CEO's and they all decide not to undercut each other" which is a pretty specific presumption. One can be suspicious of something without having any actual evidence of course, but if you're going to share your suspicions on Hacker News I think it's reasonable to expect to ask be asked to substantiate them.