Because there's immense suffering all over the world. Horrible things happen to people every day.
Why do you want a painless way to die? You only die once, right? Why not die the most horrible way? Thats what I always felt. Lots of experience comes from suffering, unattainable from any other way. From suffering comes respect. What youre saying makes it sound like you don't have respect. Fuckem dude. There's lots of things you can do out there that nobody else will ever do. What do you have that most people won't give up? How can you alleviate suffering of other people? You don't have to simply die. It doesn't matter if someone in particular respects you. Plenty of people don't respect someone for illogical reasons... Even family. People are murdered by their own families for being who they are.
If you really feel this way, dedicate yourself to other people's lives. Don't take the easy way out, man. Its easier said that done but you might respect yourself more after. There's nothing negative with doing good is there?