Did you also find wallets with any balance on it? Would be interesting if people still use them.
No I didn't. It seemed to be a lucrative business once so I can imagine lots of time and computing power has been consumed to find private keys for addresses with non zero balances in the past.
Furthermore: I'm just interested in finding as much brainwallets as possible which have been used in the past. I'm not interested in stealing funds which aren't mine.