I hope your use of "creativity" was not to imply the fiddling of the numbers.
It is very hard to figure out how to adjust the CPI over time; some things in the basket decline in volume (more efficient cars need less fuel per mile driven, but then again have people also changed their driving patterns or not?) and of course products switch in and out (who buys ring binders any more but of course a smart phone is a pretty necessary purchase yet didn't even exist 20 years ago).
Also you want to record the influence of high frequency signals (volatile commodities) yet damp it so it doesn't cause noise (fluctuations) in the signal.
Any then there are wholesale service changes (people eat out a lot more; when I was a kid I hardly knew anyone who could afford to eat in a restaurant more than once or twice a year).
There's a similar problem with GDP but GDP is so stupid that I don't care about that. It was "designed" (actually just spontaneously thought up by Kusnets) as an interim way to get some idea of what the hell was going on in the economy using just pencil and paper until somehting "real" could be developed.
And on top of that, CPI is not just some politicians deciding what they want. It is long term employees at the Fed and they take their work very seriously. They choose thousands of specific products from randomly selected retailers and they literally call on a regular basis to check the price changes over time. They keep these specifics top secret to reduce the chance of meddling. The kind of people that do this are the real "deep state" and they are the kind of people that actually keep our government working.
