Bring me the data sheets! I wonder where I am? I'm a casual that certainly follows the mentality of "elite." I am an elitist (not the bastardization it has come to mean 'believes they are superior while others are inferior'; I mean 'this is the game, perform what the game wants, get better at it, get better at it still, continue to get better at it because you will never be perfect').
Also, Omega normal is a far cry from the highest denominator expected out of this game. What I am not saying is it's easy for everyone; I'm sure my mother with arthritis would have a hard time playing the MMO, but I'd not demand they dumb the game down for her; I'd actually point her to a game she'd be able to handle. However, that's someone with a physical handicap and disability, which is far harder to overcome than something that usually equates to laziness. Most players are capable, just unwilling to improve. What I am saying is people should look to improve, not try, fail (or are now 'inconvenienced') and ask for something easier. As long as you continuously give in to make things easier, there will never be a need to improve. The goal is to make skill gaps shrink, not cause reasons for them to gape.
That's a misconception. In normal modes, you do see extremely simplified mechanics of the savage or extreme versions. IE: Sophia normal teaches you to go to the side with less weight so you don't slide off. Extreme takes the same mechanic, adding in slightly more difficulty with the two different weights. Ramuh's fight is essentially the same exact fight, just with water, making the area smaller with a forced tank swap because of the orbs. O1S and O2S are barely different than the normal modes. Even A11 with the prey mechanic is no different than A11S's whole party is now at 1 HP, floor lines so you can't stay in place and the boss is now casting an AoE, better heal up. The difference is that it's one person with that mechanic in normal with the same variables, and in savage it's now on the whole party.
The 'no bonus' thing is for players that simply don't want to carry people that may not know anything about the fight and waste their time. This is generally people looking to farm the mounts, but not always limited to that. The raid finder had the same option as well; clicking duty complete means you could not get someone with a bonus; the difference between a PF with no bonus and RF with complete meant that RF was new people every time and PF was the same 8 people. Some people just like the appeal of consistency that PF group would bring.
The reason people give those that sneak into party grief is because they often don't ask. This, regardless of your culture, is generally regarded as disrespectful. Many parties that are asked will give the person a shot, but will only give them so many tries. If it's not the person in question messing up, they often will keep them and remove the player(s) causing the issue(s).