Thinking this through for a minute, it seems like the obvious answer would be: let people choose either (say) $500 ticket price or $1,000, and also have a note saying “If your annual income is above XYZ, we would like to ask you to choose $1,000, though this will be done on an honor-code basis. If your income is below XYZ, feel free to choose either option” (or something like that)
Thinking this through for a minute, it seems like the obvious answer would be: let people choose either (say) $500 ticket price or $1,000, and also have a note saying “If your annual income is above XYZ, we would like to ask you to choose $1,000, though this will be done on an honor-code basis. If your income is below XYZ, feel free to choose either option” (or something like that)
Yep — this is basically my preferred option right now for what we should do (transparent options/honor-code basis).