I can only speak for myself, but the people I compete against are very, very well off. Lawyers, doctors, dancers who have wealthy parents/spouses, dancers whose parents own/operate dance studios, wealthy grandparents, etc. It is very daunting to find yourself the only one who is struggling just to find the extra money for gas to get you there. Nevertheless, I have beaten the best, so it goes to show that even the poorest dancer out there can overcome what seems to be insurmountable odds.
As to your question, "will this sport eventually be just for the wealthy?" I think, for the majority of dancers, it is a sport for the wealthy already. All you have to do is look at the price of dresses, lessons, tickets, fees for coaches and realize that an average comp can set you back 3 to 5 thousand dollars, to know the answer.
"Is there anything we can do to make if affordable for all?" I think the answer is no. How do you convince a pro to lower his/her fees, when there are so many willing to pay what he/she wants? How do you convince the dress designers to lower their prices, when someone will come up and, without batting an eye, buy three dresses at once? How do you convince the photographer/videography to slash their prices? The answer is, that you can't. It's free enterprise and the dancer is basically at the whim of ballroom pricing.
I have had a very difficult time paying for my ballroom dancing. I work and every single penny goes into my dancing, which I hope will someday be my career. I have sacrificed a lot for it. Am I bitter that I have struggled so hard, while watching wealthy dancers get carte blanche? Of course. I'll be honest..it stings. But this is my life, my situation, and I have faith in God and myself to get me where I want to go. I like to think that I am in a refiner's fire right now. I hope that my hardships will shape me into a better person; one who, if blessed with a dancing career, will be able to remember what it was like to struggle and be able to help the less financially blessed dancer.