What's the point in brute forcing all of these addresses. Aren't they empty?
The puzzle was made long ago and it looks like it was meant to have more and more difficult solution for each "new" address towards the end.
It was not like that, the addresses following a certain rule were all emptied and for the rest the brute force is being used.
And since, as I said, it's more and more difficult, not all of them were found/emptied yet. There are a couple of threads made on this topic, at least one of them is still updated regularly and you can see there what addresses still have money on them (or you can look on the blockchain, obviously) and how some even try to team up the find the next address' private key.
And no, it's not 100% pointless, although they burn a lot of electricity for this. Each new address holds a higher amount of BTC and with the price going this high they can pay for that electricity and also get profit... if they manage to find the key.
PS. Scroll into this list and you'll see that 66th entry has no solution found and 6.6 BTC prize. Do the math.
