Firstly, I haven't read the last 5 pages of this thread so I apologize if this has already been mentioned.
What strikes me as odd about the rogue is that there are only a few common ways to differentiate him from a fighter, he can either be a strong DPS or he can be a strong DOT. The OP obviously doesn't like the idea of a rogue being DPS because he/she feels that there is no reason that a fighter should not be able to do everything a rogue can. The issue I see with that view is that the only combat viable way to play a rogue (and while I recognize that in a good pnp or even computer game there would be ample opportunities for a rogue to flaunt his/her skills such a perfect situation cannot be assumed) would be to work with the concept of "bleeding wound," where the rogue darts into combat, strikes an enemy and then runs out and waits for the enemy to either die of blood loss or become weak enough that he/she can then dart back in and finish him off. While I think that this concept of rogue is both interesting and more realistic, (it would synchronize well with the poisoner archetype) at least in d&d it does not work well at all. This is because in d&d lingering damage is just too low to be viable. If P:E changes this I think that this is another way to play the rogue and while, in theory, a fighter could do the exact same thing, he would have no reason to do so thus providing the rogue with its own combat role, albeit a niche one.
The problem with this is that it's difficult to make damage over time effective enough to merit its use. While you can kill an enemy with a minimal amount of risk using this tactic, it is also extremely slow and prone to being heavily overshadowed by the fighters ability to take down the enemy in two hits. Unless you can provide an AOE version of the standard DOT effect anyone capable of fighting will do something else and the rogue will still end up as an inferior fighter.
On another note, I have never personally experienced a situation where the rogue ever really outshone the fighter with regards to damage (granted my experience lies solely in 3.5e so I can't comment on 2e or 4e). In general I feel that sneak attack is more of a consolation prize for the rogue. Unless he has hips or a bow he has to be in melee range to use a sneak attack and with the exception of level 1 enemies, he almost never brings them down in one blow. Unless my DM is much crueler than yours, the first thing most enemies do after the rogue sneak attacks them is turn around and attack him, so the rogue has to immediately run away. Even with a bow he has to be within 30 feet to sneak attack and so the enemy can pretty easily attack him afterwards. So while in theory a fighter would be capable of doing a sneak attack, I believe that from a game-balance perspective the rogue does not gain untoward power by possessing it while a fighter of equivalent level would gain a much larger benefit. I could support these views with numbers but this post is already pretty wordy and I don't really want to run the calculations.
To conclude: d&d values damage potential, and so rogues possess sneak attack in order to allow them to play a skirmishers role in combat. Despite this they still do not generally outperform their peers (at least while reliant on sneak attacks, umd and other skills tend to be far more potent) so while realistically there is no reason for a fighter to lack sneak attack abilities, from a balance perspective the rogue class requires them (at least for inexperienced players).