I joined HN fairly late (just a few years ago) and my subjective experience of the rules (as they are lived) is that a 'thanks' comment is almost invariably countered with a snarky 'that is what the upvote button is for' response.

For what it's worth, the vast majority of my experiences here on HN have been positive, and I greatly appreciate how often someone with significant domain knowledge turns up and replies to me in a way that seriously challenges beliefs which I had previously taken to be fact.