You're right that people are always going to be offended, that is inevitable--but screw is a euphemism for fuck, which is not the same as rape. It does not trigger the same emotional response in a victim of sexual violence that the word rape does. You can't eliminate every word, but you can try your damnedest to not use certain ones if they hurt people.

As to ignoring ppl that say it--oft times the damage us already done, it's a trigger word. You can't ignore a gunman if they point a gun and pull the trigger, it's the same concept. I dealt with a young girl who was raped by 3 school boys a few years ago and she was fragile as hell, you think if she's in a raid and someone says rape she wouldn't immidietly think of the events they occurred that dark night? She might not say anything, she might tough it out...

but wouldn't it be better if the trigger hadn't been pulled?

As for self righteous...

self-right·eous (slfrchs)
adj.
1. Piously sure of one's own righteousness; moralistic.
2. Exhibiting pious self-assurance: self-righteous remarks.

probably so, I'm not pious--I'm an atheist, but I will vouch for my morals. I try to make the world around me better. I defend whoever I can, and I am not ashamed of it. You and anyone else can call me names for it, but if you don't stand for what you believe in you will fall.