I think this would be a bad idea. Yes, it opens up potential for abuse. It also encourages multiple accounts, which we do allow sometimes but I don't want to encourage it.

There's so many limitations that would have to be placed on the account, which is a lot of coding burden. We'd have to define a whole new type of account, which is impossible to be logged into with standard ways. The group account would have to be blocked from the majority of website features, like voting (which would break multi-account voting rules), or messaging / commenting (which would create anonymity problems).

The game interface would also have problems. You could just add a dropdown when saving, I guess. But what about commenting, to what extent should that be allowed on the group saves, do we need to add an account selector system?

I'm sure I could think of more problems, and probably more solutions. But basically, it's not something I'd want to tackle.

If you're thinking of creating a group account, I'd really discourage it. Sharing passwords is against the rules. You could upload group saves yourself and give credit in the description, though. Every group account in the past that I know of eventually got banned, usually for multi-account voting.