Wild yeast is everywhere, and very different from place to place. To my understanding a little jar of one culture stands no chance against the evolutionary pressures outside it, so within a week or two an imported starter will return to whatever yeast exist in that specific area.
Trading across villages would be a really good way to keep 'new' flavours coming in :)
For example, I prefer slower rise times, my doughs frequently ferment at room temperature for 24 and even up to 48 hours in extreme cases and still produce nice bread.
I do this for aroma but also for convenience. I like to be able to shape the dough in the evening and don't worry about it and put it in the oven in the morning. It grows so slowly that it can easily accommodate few hours of change in schedule or 1 or 2 digrees shift in temperature.