You have to admit, that's pretty awful. There's only a 20% difference, is that so?

Fear not! The 28% difference in the average meaningless. The difference I see in that quote is (90-30), which isn't nearly so bad - and the "1" is also rather telling. More importantly by contrasting the averages with the medians and quartiles we can get something of a picture of what the data looks like. Enough to make a guess as to how it would change if we cut the noise by sampling only, say, those with >= 200 reported karma.

(Note: I am at least as shocked by the current downvote of this comment as gwern is by his "20%", and for rather similar reasons.)