Those who need God more seek Him more. Those who are "self-sufficient" don't bother with God except superficially.
An article by Religious News Summaries:
Recently released data by Gallup reveals that religion plays a greater role in the daily lives of people in poor countries than those living in wealthy countries. Christian Today reports that 84 percent of adults in 114 countries say religion is an important part of their daily lives. In countries where per-capita income hovers under $2,000, that figure jumps to 95 percent of people. The percentage plummets in more wealthy nations. In countries where average per-capita income is above $25,000, just 47 percent of people say religion is important to their daily lives. In the United States, 65 percent of people said religion is important to their daily lives. In Estonia, only 16 percent of those surveyed agreed. Gallup said the survey results could indicate that religions plays a "more functional role" in poor countries by "helping many residents cope with a daily struggle to provide for themselves and their families."