The bottom line is no you don't have to be rich to own a Class C. You can go out and buy one for $5000-10,000...Granted it wouldn't be one that I would want to drive or stay in, but to each their own.
But don't think about going into RV'ing if you are thinking it will be a cheaper way of travel. Most important is that initially it will not be. Considering the money you spend on your RV, maintenance, taxes, registration, fuel costs and money you will sink into gizmos, gadgets and thinks specifically for the RV. While you can often find a half way decent park to stay in an area you might want to visit, often it's a different situation. You may end up staying further away from your destination than you intended. Or you may pay a high premium for a parking spot in basically a concrete parking lot.
Consider it an expensive hobby. When people compare RVing and staying in a hotel, they mention about food costs. When we RV, we don't eat soup or hotdogs everyday. WE may have hotdogs or burgers once during a week. But usually it will be steak or some sort of seafood. Otherwise, we enjoy going out to eat and checking out some of the local eateries. We don't prepare meals ahead of time and freeze them (although it's a good idea). We RV to get away, explore and have fun.