When you generate a new bitcoin address, it only takes disk space on your own computer (like 500 bytes). It's like generating a new PGP private key, but less CPU intensive because it's ECC. The address space is effectively unlimited. It doesn't hurt anyone, so generate all you want.
Though i'm really in no position to engage on the debate of bitcoin address against generic variability. All i know is that one person can have a multitude of wallets as he wants, that's pretty enough for me. #winks