McDonalds isn't a fast food company. They are a real estate investment company. Their former CFO said as much "we are not technically in the food business. We are in the real estate business. The only reason we sell fifteen-cent hamburgers is because they are the greatest producer of revenue, from which our tenants can pay us our rent." - Harry J Sonneborn

Same reason you see so many neutral colored cars these days. People used to have colorful cars because they were buying the car they'd be driving for years; now they get soemthing they know they can dump.

Problem being that even when they try for that, near as I see they are still just as prone to demolish it and rebuild anyway. At best the framing is retained, but they rip everything out including the drywall and renovate.

Or the customers who were children grow up?