There's no reason to respect a position if promotions are handed out like candy, either. Heck, I've had harder times getting candy. I don't get a job at McDonald's, serve one customer, and get promoted to manager. What's that? I fired one employee? Great, I am now the CEO. I've heard Skyrim will involve random quests. Hopefully they apply this to factions, and make you work for those promotions. Do enough work and maybe you can choose to receive a special missions or task for promotion. Maybe I don't want to be the top dog of the Fighter's Guild, maybe I just want to go there to do work I can get paid for, like everyone recommends it for. I'm sure some people would like to be able to stay at a certain rank and do quests as they please, instead of either tearing through the linear storyline or having no FG experience at all.
The game has obvious limitations. And some of them are only reasonable. Do you really think you could finish up some of these main quests in the matter of days to weeks in which we so often do? If any of the quests really took months to years to accomplish, very few people would actually appreciate it. It would detract far too much from their actuall lives, place too great a demand upon them, etc. The notion that guild mastery should be as involved and elongated as such a thing might be in one's actual life is like suggesting that a film actually last the length of time it would take for the events in it to unfold.
Also, the Mcdonalds anology is not apt, and the accomplishments listed therein too commonplace. A junior executive managing to become CEO in a short span after landing a series of major deals and related corporate victories is more anologous, but still not entirely on keel. In ancient times, especially if you go back to times of tribal war etc. a series of major battle victories could propel one very high very quickly were they significant and sweeping enough. Rising to the head of the guilds in ES usually involves accomplishing a series of feats that no other in the organization has managed to do. Consider, by the time you near the end of the guild sidequest, you are privvy to sensitve information that few others have, you know secrets, often about the guild members, that few others know. . . there is a good chance that you are both too damned powerful and too dangerous for the compromised members to attempt to kill ( these people know you have likely already triumphed against circumstances and adversaries they likely would not have been able to even survive against). . . Coups do happen. Upstarts sometimes overthrow entire governments. . . You are a hero and a legend in the guild by the time the quests are over, your deeds legendary, your talents, powers, and even your strange good fortune, are also legendary. . . would the beuracrats really want to stand against you and deny you the position that you are vyying for, if you desire it? Who among them will be so bold as to spit into the face of the hurricaine, to stand against the Guild's new champion, before whom all other enemies have fallen or fled?
It might be a little like what Aragorn once said to Frodo, " If I wanted The Ring for myself, I could have it. Now."