Weird, that. The only instance in which I can understand "no sex -> no lust" formula is when a person is a virgin (like Cali and Zoe in my game). You can't miss what you've never had.
(Good idea about a celibate team, why haven't I thought of that? Though while I level up Cali and tame a captured lvl 11 arachna to replace my guys in combat, I'm stuck))