I know a few people that play higher limits, but go down to the penny limits to blow off some steam after a bad beat, or to loosen up after playing their A game for hours at stakes that matter. That might explain some of those players.

The rest? ... Well they probably saw poker on tv for the first time and saw Gus Hanson make outrages plays, or Danny Nguyen lunchbox his way to a WPT title, and naturally assume that is how poker is played, without excepton.