Don't know if he picked it up just from seeing others use a similar line of argumentation or what, but the general 'other cultures' argument is very commonly used by industry to counter animal and environmental activists. See native trappers/hunters (apparently the commercial fur industry loves these guys), logging communities (the logging industry are their best friends), traditional whaling communities ... Often these concerned industries drop the charade and flat out abandon these communities when they are no longer useful.
Broaden the focus a bit but keep the claim being leveled. Any viewpoint that denies me the right to voice objection to say honor killings (the murder of a rape survivor by a relative as punishment for dishonoring the family by being raped) or female genital mutilation to cite two 'cultural traditions' is not acceptable. Any obligation on me to respect traditions or ways not my own is trumped by my obligations as a human being to speak out.
Dave in MPLS / DISCLAIMER: I am not an actual rooster.
"It is better to light a candle than to curse the darkness"
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