Cave hiking is considered to be an extreme sport in some circles. However, extreme sport tends to mean that the people who participate have little regard for safety and that is not true with cave hiking. Cave hiking is a recreational sport that is quite challenging and requires skills of varying levels depending on the type of cave you're exploring.
Hiking boots need to be good. We are walking great distances often over treacherous terrain in all types of weather. They need to provide support for the feet, be comfortable and most of all they have to be strong.
But this does create a problem because good quality hiking boots are not cheap. Far from cheap.