The internal cost of cheating is usually unacceptably high; it makes me feel bad! It makes me feel bad, because I'm violating my own sense of what is "right". If my morality says it's okay to cheat, such as declining small talk and continuing to read my book, I'm totally okay with it.

There's also usually very minimal benefit. Of the examples listed, "tipping" is the only one I'd be genuinely tempted to avoid if I could, except that it's a social norm here and it would therefor effectively be stealing (by my own morals)