Living at the end of the line alters your relationship with the subway. You rely on it’s presence and emptiness in ways that would not be appropriate in the middle of the city. There is also a level of accumulated filth at the end of the line that probably does not apply there either.
On weekday mornings, after the train empties out, somebody takes to the train with a mop and bucket and slathers chlorine on the floors. The odor is stiff and intense and often, but not always, worse than the filth. At rush hour, the trains are moving in and out too quickly for all of the cars to receive this treatment. So you can weave through the waiting train searching for a car that doesn’t overwhelm you one way or the other.