"Christian ideals" do not necessarily mean the same thing as accepting Jesus Christ as the Messiah/Son of God. "Christian ideals" is shorthand for the things Jesus taught. That doesn't mean you have to accept him as anything other than a guy who had some lovely ideas. Even people who don't think he's the Messiah still think he existed - i.e. he's not a legend like Paul Bunyan.
Christ is one of our exemplars, and even with that, at no time and nowhere in the member education materials or the ritual do we say "Jesus Christ
is the Messiah and the Son of God." We say "many
believe him to be the Son of God." Hermes is one of our exemplars too and we don't have weekly meetings to pray to Hermes.
As far as the chapters having Bible study, I've already said that I don't really dig that concept, but apparently in the South it's the rule rather than the exception. However, if you're at a campus where there is ONE sorority who has Bible study and no one else does, I would take that to say that if you're a non-Christian in this group you might not be comfortable.