Of course moral positions can be expressed in licenses. Licenses are just contracts, and if your don't agree with my terms, just don't use my software.
Your statement only becomes true if "open source" is a premises.
Also, moral positions could be expressed in copyright law, if wanted. Just imagine a copyright law not granting copyright on religious works. This would be a quite laizstic(?) copyright law.
@jwildeboer @risottobias