Firstly and probably most obviously, their business is based almost in its entirity around a single third party open source tool, without which they would have

Firstly and probably most obviously, their business is based almost in its entirity around a single third party open source tool, without which they would have nothing at all, and yet their site is not open source. I know they have every right, legally, to do this, but to me it seems .. exploitative. they saw a market nobody was catering to, and despite being based around a free tool, they're not just exploiting the community. they provide a lot of free git hosting for a lot of projects, and you have to give them some credit for that. and as far as i'm aware, most of their site is based upon a ruby re-implementation of the git tools that can manipulate the git meta files. that was written by someone involved with the site and is open source, so they are also contributing back to the git/ruby community that way.