well, just for the record, I do, and I've also worked for the body that calculates our CPI. just before I left we were studying how to get what we call "administrative item data" from the retailer's themselves rather than relying on surveys, household interviews, internet scrapes or staff research. To be fair, CPI was never my specific methodology speciality, but I can talk your ear off about household incomes, relative welfare measures and theoretical probabilistic data linking and entity resolution :) (I've also had a finger in the pie of a lot of other measures even though I wouldn't call them my speciality, but I'll wager I've got more experience than 99.9% of hacker news in this regard).

honestly, as someone who's had to put together official stats, I'm almost always disappointed to hear the conspiracy theories and methodology misunderstandings in the general and tech community. back in my day when the government wanted to do actual conspiracy they just cut the funding for measuring/recording something. but instead we get "CPI is rigged", "do you know what the REAL unemployment rate is" government-manipulation ignorant memes.