Bandwagon argument. If someone were copulating in the street, you bet they'd get busted for sodomy, plus everything else. You ignore probable cause. Two guys sharing a house isn't probable cause. Two guys holding hands at the dinner theater isn't probable cause. Probable cause is the neighbor complaining on the phone to Police Dispatch that her neighbors left their back gate open and she can see them copulating unnaturally in the back yard.
Laws about public sex apply equally for everyone, anyone would be busted for copulating in public.
"...copulating unnaturally in the back yard."
That has nothing to do with the issue at hand.
That is also public, not private behavior.