Bitcoin is decentralized and that is why it is hard to gather statistics as to what purpose does the bitcoin buyers why do they buy bitcoins. Also there is no analysis reports, if bitcoin is decentralized who in their right mind will handle that task and who will pay them for doing so. Hence, it is impossible for us to know those things especially those peer to peer transactions. But if you are really interested then you can make some polls to have a rough data and statistics here in this forum, though the accuracy is far off from the real events but at least you can gather some data and have a better understanding about bitcoin transactions.
i guess you miss the fact that blockchain data is clear to see, you can easily see where coins go.
for instance. some pools move coins in large clusters. some make a transaction paying out to lots of little amounts.
its easy to spot differences where say slush pool is paying out to individual hobby miners their small amounts or paying a large player a single large amount
you can then follow the spends to see how long it takes and how many spends it takes to then end up in known exchange cold wallets
add to that when main pool owners do interviews they explain their business models and even laugh when people presume that large pool owners sell on exchanges and be held to the whims of such volatility.
yes the little hobby miners that only earn a few crumbs an hour are too small to even bother investigating, plus their crumbs dont have much impact to b of concern. but the bigger pools do actually talk alot about how sustainable their business models are.
some unrelated stuff i found funny when looking into pools handling of funds.. couple years back the propaganda machine was rampant. there were pools like slush pool who were very vocal about their love of segwit and then the propaganda machine saying btc.com was very much anti-segwit.. funny part is 2 years later and slushpool put their coin rewards on legacy (1) addresses and btc.com put them on segwit(bc1q) addresses
and on unrelated note i still see peter wuille who developed segwit still prefers to accept donations through a legacy address
all im saying is there is quite alot you can actually learn if people actually bother to investigate/research.
too many people still think bitcoin is anonymous and no info can be found about anything..