Well, the real problem is that for many people that have already cleared that content and, as such, have no need to run it again, it's just more trouble than it's worth to join groups that likely won't make it ( or it's worth 10's of millions of gil; depends on who you ask). You can't really fault people for trying to enjoy what time they have playing the game. At the end of the day, these "no noobs wanted" farm parties and the OP are after the same thing: a sense of progress. There's just not much incentive to help random people struggling with old content.