Apparently it's an exclusion only with career patrols. According to
this UBI post you can abandon ship/surrender in single missions. I've never played a single mission myself, so can't confirm.
trenken: abandoning your boat and at least surviving is perhaps better than the alternative... and yes, whilst it might be pointless in the game (you die/surrender, same thing, career over, start again), those who play SH3 as a
simulation see it as a bit of an oversight, so much so that SH3Cmdr includes a workaround which allows players to change a "dead" career into a "surrendered" career, if the player was on the surface when they "died".
Perhaps to draw a comparison, when's the last time you played a combat related flight simulation that didn't allow you to eject? Same thing.