We've heard arguments thats its "because of budgeting", "because of different projects", then its because of Coinbase.
But now it seems, that small amounts are being transferred into Binance in the end, around 4 ETH each.
It is interesting to note, that on Binance, you don't need a verified account for transferring of small amounts (24h Withdrawal Limit of 2 BTC).
This looks a bit suspicious and there doesn't seem to be any valid explanation so far.
But do your own research and make your own judgements
