it is not just privacy reasons, there are more to reusing the same bitcoin address more than once for receiving multiple deposits. for example the biggest problem most people will face these days is the higher fees.
read this:
https://en.bitcoin.it/wiki/Address_reuseI do agree that using multi address nowadays in transactions would be not beneficial though it doesn't change the fact that it will really offers you to be more private. Though I know a wallet that if you transfer Bitcoin to the same wallet it has no transaction fees only applied for external wallets unlike in Mycelium which you can create multiple addresses but if you transafer it to another Mycelium address you made, it has transaction fees.