Hi everyone - I thought I'd chip my bit in... St Nicholas may have been the area's equivalent to Manchester Cathedral in that it was much cheaper for marriages than the local parish church was, so folks flocked (to the Cathedral) to marry. I believe that Moxley's parish church in the Darlaston-Willenhall area also provided a similar cheaper marriage. I have ancestors who used each one of the three, despite living within another parish church boundary.
All the best, Anne.