What incomes do people have to be able to afford international first class plane tickets?

If a flight to europe is 1,400 in december (~5,600 for a family) & first class would be ~25k that seems like you'd need to earn at least $500,000 a year? I know you'd simply need the money (like a rich person who doesnt even need to work) but in this case I'm asking about those with a certain amount of income per year to be able to afford this.
Added (1). I don't know why people answer the question to comment. Larry, that's implied/ common sense. A more logical answer - "if your mortgage is xyz, and personal expenses xyz, yes you would need maybe 600k a year to afford that"

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