Between advertising, promotions, video production, team salaries and miscellaneous costs, I’m guesstimating that Etnies puts over $20,000 a month into BMX.
Yes, they do also support skateboarding, but to assume that Etnies money goes solely back just into their skate programs is inaccurate.
If you really want to support a company that will insure your money goes fully back into BMX, and that actively supports the BMX industry, Orchid would be your safest bet.