Branding in desktop games

I wonder how appropriate is to use themes for the games in GNOME to "promote" a distro. I was told by someone to send such themes upstream.
Now, if i would be the upstream maintainer, i would feel the need to be distro-impartial and reject such contributions, this is why i am reluctant to propose those upstream.
But i, as a theme creator, i am not sure creating such themes in the first place is a god idea, still weighting it. Opinions?

Anyway, just for fun, i did such a theme:

This Same GNOME theme is available for download.