no they will never die
muay thai is traditional.
krav maga is not martial arts. i doubt a hapkido instructor would switch to that unless he was an incompetent one. as hapkido has a lot more realistic techniques the krav maga.
krav maga has few techniques and most people that teach it add other traditional arts to it.
http://www.bullshido.net/forums/showthread.php?t=13414
http://www.bullshido.com/articles/krav-maga-3.html
you want to talk about realistically krav teach how do deal with grenades and suicide bombers, how often do you come across this.
as for mma, mma is a sport and not martial arts. i would take this over krav maga any day of the week. it is far more useful
contrary to want the kids on here say 90% of street fights dont end up on the ground. in a street fight there are no rules other people tend to jump in, so the ground fighting is not always the best for streets, it has its place, but not always in the street.
you should try learning for a better instructor. i've been using shotokan to defend my self with few issues for 30yrs
參考: 30 yrs ma
shotokan and shito ryu