My 2cts:
I fly at Livermore, CA which has two parallel runways. If I'm on base and I don't get a clearance to land my choicees would be:
1. Straight on and do something else - not possible as I will cross the centerline of the other runway.
2. Turn downwind (away from the runway) - sets up a conflict with other people on final
3. Turn final and do a go around - the only sane choice. I'd add that I'd also sidestep the runway (away from its parralell neighbour) so I can see it.
theRolfe