I'm inclined to agree, however if you remove the feelings from the situation - it doesn't seem much different to any other contractual obligations - like the amount and frequency of their wage payments.

If your contract stipulates that you (and your employer) should "do no evil" without supplying a definition for "evil" then it really isn't that much different to any other contractual breach. Also, you'd have to be stupid to put that in an actual contract.