Oldest 25? I think you are missing the core group that are driving the sport. Wakeboarding will be driven by the 25 to 45 age bracket that purchases boats. Cable park or boat, this hobby is driven by the the demographics that can afford boats, plain and simple.
I wanted to fill out the survey, but even if I was under 25, I was to busy with partying to be online filling out surveys. I truely think any survey would be thrown off, as you don't include the majority of this sports market.
Not to exclude the younger crowd here, but I'd bet the average age here on Wakeworld is 25+