I lived near a small historic town with many buildings standing since the 1850s. Tourism is a HUGE industry that brings in dollars to local businesses. It's in the town's interest to preserve that income, so they mandate color and style codes for new buildings as well as restoring older buildings. This is complemented with many folksy festivals and re-enactments as part of drawing in tourist dollars.

When people balk at these codes, and they do all the time, there are several other larger and modern cities nearby where they aren't restricted in any design sense.