I've posted often that there is a ton of science behind the OLM on GM vehicles. There is still a lot of skepticism based on the "old school" and personal history.
I still go to get the oil changed in Mrs. Number 3's Malibu. She has 100 mile highway commute and the OLM will easily go to 10,000 miles. I always get the, "ohhhhhhhh, you shouldn't wait so long to get the oil changed, it's verrrrrry dirty". So someone less technical or without the belief in the science might be scared back into the 3,000 mile change.
GM never really got the credit for this, but their point was to be greener by changing your oil as needed, not at 3,000 miles "just because".