yes they can
no they cant
The fact that your raid could theoretically end up with 25 items from one LFR boss with the current system makes a pass option rather useless unless it actually gives another person two rolls.
I have yet to see a single suggestion of changing LFR loot system to have a smaller chance of gearing up.
Every single thread can be summarized in :"Moar Loot!!".
This one,as an example,you would eventually get loot that another person passed on.
This premise is the problem in most of these kind of threads: Blizzard has stated that this system offers a gear up rate equivalent of the normal raiding system and they are ok with this so any kind of suggestion for a better LFR loot system should focus on that "Better" not "More" or Blizzard will just ignore it because theres a finite number of carrots.