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My girlfriend and I went out to eat with an acquaintance of hers and his wife. They were really nice people, but at the end of the dinner date, they brought up a known pyramid scheme that they're a part of. They asked if we had ever heard of X corp, to which I replied "yes". When they asked me about what I knew about them I lied and said "not much". However, I actually know a lot about them and how they scam people shamelessly.
Then dinner eventually ended with us saying we'd think about it and get back to them. What's the nicest way to turn them down? I'm not opposed to calling out the scam, but I know from experience that people get very defensive since they've invested a lot of money into the scam.