Oh man, the thermostat wifi thing is your answer right there. Once someone starts connecting totally unrelated stuff into one big plot, the debate is over and you just nod and change the subject. Here's my line: if they can point to one specific thing and say "explain this," that's a fun talk. When it turns into a whole binder tying everything together, that's a sign they've gone past debating into believing. The flag thing gets tons of people because it looks like it's waving when there's no wind, but the simple answer is the astronaut was twisting the pole to get it in the ground and it stayed wrinkled from the trip. I'd keep Thanksgiving peace by asking him about Reno or his neighbor's thermostat instead, and save the moon stuff for people who can drop it when the facts come out.

Stop arguing with the old guy, collar cuts always win.