I think the argument FOR napping is the financial one; if 20 minutes of napping gives more than 20 minutes of productivity/efficiency afterwards (which turns out it does, backed by numerous academic studies), then it is worth it.
There's a few things in American culture, in particular, working against it though: our backwards cultural attitude that sleeping is considered "lazy" (USA is one of the most sleep-deprived population) and the fact that working on little sleep is falsely considered a "badge of honor," even though the occurrence of mistakes made by workers is MUCH higher when said workers are sleep deprived.
