Do you have any evidence of that? I know about the address that was found in both the Foundation wallet and as a DAO holder but I haven't seen any other developer shown to be DAO holders. Stephan Taul would obviously be a big DAO holder as one of the people behind it but he's not with the Ethereum Foundation anymore (having left to work on Slock.it and The DAO).
Even if they have a conflict of interest they seem to be going out of their way to let the community decide what to do.