Who the fuck can afford that?

The fact that you struggle to imagine that these people exist in large quantities tells me that you haven't actually fully understood the power distribution of who is consuming how much.

On CO2 emissions, the top 10% emit about 48% of the CO2. The top 10% of Americans (where the cutoff is about $135k) produce about 55 tonnes of CO2 per capita per year, and they have low birth rates.

people with kids travel by plane too

Yes, but paradoxically having more children makes households consume fewer passenger miles at any given budget, because traveling with children is slow and less enjoyable, and their tickets are just as expensive. So the DINK couple with the $200k budget can fly for vacations and even weekend getaways once every few months (4-8 times per year), but after having kids might only fly on one trip per year. Even with two kids, doubling the number of people in their household, they might be looking at half the passenger miles by taking 1/4 as many trips.

And if eating all the meat in the world and throwing food in the trash and using disposable diapers doesn't compare at all to the consumption involved in traveling out of town by plane, then adding up all the day-to-day stuff the family is doing with kids won't compare to the jet setting couple with the same budget.

Throw in the fact that the people who have the $200k+ budgets are less likely to have kids, and you have the correlation where consumption is negatively correlated with fertility/household size.