If all religions are given equal weight, what makes the “top 3″ so enduring?

Green Pagan 4.0 asked:


In America, we have had freedom to choose our religion for quite some time - but Evangelical Christianity retains it’s dominance without much fuss…

In China - the government is almost completely atheist and trades with America and has mostly Christian missionary opportunities. But Buddhism is still growing very strong despite the government attempts to wash it away…

In the middle east, Islam is the word of the day. Even though the religion has been associated with hateful sexism, terrorism, greed and deadly homophobia, Islam is still the fastest growing religion in the region.

What causes these religions to become so pervasive in spite of the odds being against them?

Mathew