Why would anybody pay the toll if an alternate road already exists?

In the film In Time, it is shown that the toll rates are very high to get to the city area from the ghetto. But later, it is also shown that there is an alternate route for people to use which is free to use.

Why, then, does anybody need to use the road which requires payment?

• Next lord of the rings - Why did they take a Palantir with them when they left on the last ship going west to the Undying Lands?
• Previous identify this tv show - Old mech-like anime series belonging to my childhood