It was a grassroots thing at the time, but France Sr. had seen the potential of racing in the U.S., and he loved it. However, that is not the reason he started an association for car racing.
Instead, it appears that William “Bill” France Sr. was not happy with how racing rules varied from one event to another, and some promoters were dishonest on the matter of prize money.
While details of what happened back then are unclear, what matters most is what happened, which was a gathering of racing community members called upon by Bill France Sr., which then led to NASCAR as we know it.
Bill France was NASCAR's first president, and his role in the development of the sport, especially in its early decades, is essential. It all started with dishonest promoters, but William France managed to develop an idea that led to a multi-billion-dollar industry today.
The first NASCAR Strictly Stock race was held on June 19, 1949, in North Carolina, at the Charlotte Speedway. Reports from the time estimated that approximately 13,000 fans came to see the race, which was won by Glenn Dunnaway in a Ford.
He did not get to collect the grand prize, which was $2,000 (ca. $23,564 in 2021 money, adjusted for inflation), because he was disqualified because of the rear springs of his vehicle, which were not stock Ford parts.
Therefore, the first NASCAR race winner is Jim Roper, who raced in A Lincoln that was closer to what a stock car on found on any street in America that day than any of the NASCAR racers was to their contemporary street equivalents in any other day.
The process we described above is normal, and it happens in every branch of motorsport. Not even the bone-stock class is exactly stock in every competition everywhere (minor modifications are allowed—with strict checks in place).
If racing is your dream, a budget-oriented one-make series might be an idea, or you could just start racing with whatever you can afford, just keep it on the track.