Hi Wickid
The 'heat' of spicy foods is a relative thing - different people will detect different levels of heat from the same meal. It's all to do with whether you are a 'supertaster' or not.
http://www.bbc.co.uk/science/humanbody/body/articles/senses/supertaster.shtml
I love spicy foods and always go for spicy pasta sauces and chillis etc (nothing ridiculous, just 'normal' spicy options). However, my boyfriend moans that he can't enjoy the food 'cos it's too spicy. For example, if having a curry he only likes korma and finds a tikka too hot!! He may well be a 'supertaster' like your waitress?