What companies would you put in a “Higher Income Millennials” etf?

Thesis: Millennials have surpassed Baby Boomers as the largest generation in the US. With most of their prime earning years ahead, companies that cater to Millennials should be well positioned for growth. (Source: MILN etf).

I believe in that thesis, but I want to narrow it to higher income Millennials. What companies cater to higher income Millennials? (e.g. $150,000 income per person, $250k per household)?

Some questions to further discussion:

• Is there a place to find demographic of customers for large companies all in one place?
• What type of activities or products attract higher income Millennials but not higher income boomers or gen xers as much?
• Are there existing ETFs that track this?
• If you're a millennial, what are some companies that boomers don't even know existed but you think will go through the roof because of customers like you?