Again, the "all" option would mean I'm more likely to miss a particular poster I may want to quote later as I may not remember on what page I read their post if I'm trying to recall. You know how you get to read through and then you suddenly remembered you want to react to what another user said in the midst of reading another user so as to yolk both comments in your post, right? That's it.
I usually quote right the moment I feel like I got to say something, copy it in notes app, read replies again and if similar situation comes quote and copy again, once all done copy from notes app back to bitcointalk.
I do write my responses in notes app mostly as I don't trust bitcointalk editor, sudden reload and your text gone. It pisses me off. Also, undo/redo functionality in text editors really handy.