To be honest it wouldn't be beneficial this time to give away equal amount of BCC. It was okay with ETH and the classic one because the price was very low. Just imagine even if split occurs on the scale if 90/10 then also the wallet will need to give away $250 for each BTC that is held by users. Wow, that won't be profitable man.
But is that how it works? I thought it cost Coinbase nothing to give away the ETC, since the fork basically converted every ETH coin into one ETH and one ETC. The ETC was created out of nothing and was completely free (aside from the extra work Coinbase had to do to enable ETC payouts).
Similarly, the bitcoin fork will convert each BTC into one BTC and one BCC. Coinbase claims that they won't keep the BCC, so what happens to it?