What's your angle? If I put on my tinfoil hat I can think of quite a few reasons why you would need such addresses but I don't want to be accused that I'm a FUDer and a thread pooper, so here's your chance to elaborate before I post my paranoid assumptions.
Its pretty much a data I need for something Iam working on. Kind a like backtest and those kind of a info are really hard to find as people dont usually hand you over large wallets like that. So thats why Iam trying to buy some. I know this sound like some stupid scam but its actually not. If you sweep your address clean and delete it afterwards what can I really do? Other than if you had that address linked to some sort of IOU or investment.
Uhm, not a stupid scam, quite the opposite, a quite elaborate one, one which involves showing past 'investments' to gain credibility.
It's not a scam, I know what he is using them for. But I wont give away the secret. Why would he ask for EMPTY wallets if he was trying to scam people?