The current group I am in rolls need only on main jobs. After that, we just have a mutual respect for one another. If we see someone that plays a class a lot more than everyone else and nobody has it as a main or already has the loot, we generally pass. With me and the other tanks it is the same, just making sure we get geared up together. If someone is late or misses a raid, they would certainly get an ear full but if they have their reasons, fair enough because real life comes first. But should someone miss raids or is continually late, then I imaginde my raid leaders would take action, be it replacing or loot lockout for a week.