This is absolutely true. The university I went to is known for its commercial aviation program, and draws students from all over the nation and world to learn to be airline pilots. So many of them end up with huge debts, because flight school is crazy expensive, and eventually take non-aviation related jobs out of school because they just can't afford not to. Only those that were probably already very well off, or have connections, or are extremely driven, will ever sit behind the stick of a commercial jetliner for one of the bigs.