Or maybe because Vettel hasn't really had any great drives to victory. In fact, has any of Vettel's wins not been from pole?
I've heard this point brought up before and it's a valid one.
Vettel's wins:
2008, race 14, Monza - started 1st, finished 1st
2009, race 3, Shanghai - started 1st, finished 1st
2009, race 8, Silverstone - started 1st, finished 1st
2009, race 15, Suzuka - started 1st, finished 1st
2009, race 17, Yas Marina - started 2nd, finished 1st
2010, race 3, Sepang - started 3rd, finished 1st
2010, race 9, Valencia - started 1st, finished 1st
2010, race 16, Suzuka - started 1st, finished 1st
2010, race 18, Autódromo José Carlos Pace - started 2nd, finished 1st
2010, race 19, Yas Marina - started 1st, finished 1st
2011, race 1, Melbourne - started 1st, finished 1st
2011, race 2, Sepang - started 1st, finished 1st
2011, race 4, Istanbul Park - started 1st, finished 1st
2011, race 5, Catalunya - started 2nd, finished 1st
2011, race 6, Monaco - started 1st, finished 1st
2011, race 8, Valencia - started 1st, finished 1st
I was actually surprised to see that he did, in fact, win a handful from a position other than pole; four, in fact. Still, even the victories that weren't from pole were from pretty close, but twelve out of his sixteen F1 wins, or 75%, have been from pole. I haven't gotten around to comparing this to other drivers of recent years to see whether they have won more times from positions other than the pole or not, so I can't honestly say at the moment whether having 75% of your wins from pole is high or fairly normal.
EDIT:
Alright, just for fairness, I compared versus my driver, Lewis Hamilton. When looking at just his official F1 wins (not counting the 2008 win at Spa that was wrongfully stolen from him by the stewards for violating a rule they never clarified until after the race), six of his fifteen wins have been from a position other than pole, although they've been within the top four grid spots. 60% of Hamilton's wins have been from pole, and 40% have been from a position other than pole. These shift slightly if you count the 2008 Spa win, which was also from pole, although it was also after losing the lead early on and having to fight Kimi tooth-and-nail for it for the rest of the race, culminating in an exciting race finish, which is very different from starting on pole and just having the lead for the entire race. Most of the wins he did have from pole were his earlier wins, while the majority of his more recent wins have been from slightly lower starting positions.