Mainly because they're funny, but it's also because I try pretty hard to make the comment more interesting than just "here's a pelican". In this case I used the pelicans to talk about the 128,000 token limit bug at "max" and share comparative pricing.
In the GPT-6 comment I included full visual comparison grids: https://news.ycombinator.com/item?id=49805509#49806126
For DeepSeek v4.1 Flash I identified that the OpenRouter reasoning levels are mapped to a smaller set of levels for that model: https://news.ycombinator.com/item?id=49639090#49645591