if these people really were in the "we don't care about open source" corner you are saying they belong in, they wouldn't have put things under an open source license that would allow you to fork the code either.
building the defaults to use google but allowing you to fork it to use whatever you want seems like a very reasonable thing to do. most people wouldn't use the fork because they don't have the alternate servers in place to support things (and if you don't trust google with the data, why should you trust any other company?) but those that do can either fork things themselves, or use a fork that someone else has created.