the scenario i pointed out aren't "omfg dying emergency!!" but it's definitely something that would make the life of the person trying to reach you so much easier.
from what i've read, it seems like you have the cellphone for the convenience of yourself and no one else

you said you're only nearby the phone when you're expecting a (important) call, you'll only call back if they leave a message, and when you're in need of help i.e. getting stuck in the middle of the highway at midnight.
that, in a way, is inconsiderate.
if that's the case, i hope you have a seperate home-phone where people can reach you when you *are* at home and *not* by your cell; which i doubt or else you wouldn't be complaining. and it brings to another point-- you said it yourself that flashback 15 years when we didn't have mobiles. but now a days, people often REPLACE home-phones with just a cell and that's the ONLY way others can reach them. so what's the difference with people calling you through your cell when you're at home to people calling you through the home-phone?
if that's the way you utilize your cell, i think it's best if you only have your cellphone for outgoing calls and then a seperate home-phone so people can reach you at 'only' appropiate times