Here is an example from a comment on a recent Youtube video of mine about feminism:
"...a viewpoint that he claims '90%' of 'feminists' share, without offering any evidence at all. I mean, it's ridiculous just on the face of it."
The second sentence is just blatant shaming and intimidation, so there's no need to analyze it any further. My interest is in the first sentence, where he points out that I offer no evidence for my claim. Let's look at an earlier statement from the same commenter:
"Feminism has so many different forms. It isn't about man-hating."
What evidence did he offer for his claim? None of course. The reason is that he is not engaging in scientific research; he's expressing his viewpoint based on his personal experience. He might offer anecdotes and an example or two, but he's not going to have a case study handy to prove that feminism isn't about man-hating.
The point is that we all do this. It is a necessary part of discourse. It is simply not a productive use of time to catalog and detail tremendous amounts of evidence for every viewpoint we hold or express. Doing so would use up time that could be used for other things, and remove the entire benefit of having a subconscious intuition that automatically sorts through raw data in the background while we do other things.
The appeal to empirical evidence is not out of a desire to be rational and point out my irrationality, though it is his intention that people interpret his statement that way; it is out of a desire to attack my viewpoint in whatever way he can. Appealing to empirical evidence is a pwn move, basically, that can be brought out whenever he runs out of other, more productive options.
In any discussion about anything, he can always arbitrarily say "What's your evidence?" and then declare himself the "winner" when the person he is in disagreement with cannot just throw out a dozen verifiable examples. It's especially arbitrary when you consider that the level of scrutiny is entirely up to his discretion; if you can name 6 examples, why can't you name 7? Can you show me evidence of your examples? How reliable is the evidence? Etc.
At this point I can, and do, say "If you find my viewpoint unconvincing, so be it." What motivates me to write this post is not what that specific person will think, but the fact that others would read such a response as "Ooh, Shawn just got pwned. If he's so right, why can't he provide any evidence?" when it should be read as "Shawn doesn't have time for this jackass." The point of this kind of empirical attack is to make someone look irrational and foolish in the eyes of others, who might unwittingly be fooled.