I just finished an 850 mile road trip today, and along the entire route, I did not pick up a single door opener (that I could confirm, had several momentary X band hits when driving by some shopping centers on I-40). Nor did I pick up any at any of the places close to my home where I know automatic door openers to be in use.
On closer inspection, it seems many door openers have been replaced with either optical or IR motion sensors. I thought for certain when I got out into more rural areas I'd still come across some old X band or K band door openers, but even most of those appear to be retrofitted. I'm certainly not complaining, one of the reasons why I ditched detectors about 4 years ago was because of all of the K band door openers.
Before anyone asks, I know K band is working, I picked up a patrol car here in Oklahoma from about a mile coming and going when he was off on the other side of the road with a customer.