I love spicy food. I dump or sprinkle hot sauce or chili flakes on most of my meals. Almost everything I cook for myself is spicy, and I have a strong predilection for cooking Thai, Indonesian, Indian, or Mexican food. My cooking habits have adjusted quite a bit while I've been home, since some of the people I'm now cooking frequently for cannot handle any spice. (Certain individuals have tried arguing with me, saying that they do like spicy food, but no, they do not. A twist of the black pepper grinder does not make a dish spicy.)
A recent article, "Why do we eat chilli?" (also, why do the Brits spell chili with two Ls?), examines why humans, unique amongst the animal kingdom, seek out and enjoy something that is technically--from a physical receptor standpoint--painful. Is it conditioning, the fact that we've actually worked to build up a tolerance? Or some human psychological flaw, a form of masochism? Masochism, tolerance development, I'll just call it delicious and let the scientists try to figure out why.