Do American preachers recycle their material heaps more than Australians?

Listening to Driscoll @ TGC conference. Seems like I've heard him. on negatives, positives and neutrals before. Definitely heard Dirty Don re-use stuff often.

I feel like Aussie preachers do this less - is that accurate? If it is, why?

Are we more insistent on returning to the word, week after week, as a ministry rule of thumb? Are we more insistent on preparing new material for new occasions?

I do re-use sometimes, but it'd be the exeption rather than the norm. Perhaps a little bit more common would be the insertion of little 'plugins' or 'riffs' to a new sermon.

How often do you re-use? What are some pros and cons?