They do that all the time, I was stationed at King Salmon in 1979 and they will fly just inside the ADIZ and we would scramble they are just checking scramble time. We also fly KC135 out of Fairbanks and do the same thing to them. I have actually seen Russian chasing the KC135 back across the ADIZ on radar. Cat and mouse games. Lot of those radar sites are civilian manned now and the signal is sent to Cheyenne Mountain.
I was stationed in Cold Bay 1975/76 in radar ops, and I saw the same thing, too.
I still remember one of your King Salmon jet jockeys bubble checking us in an F4. Scared the crap out of everyone who didn't know what was happening.