I have had people in SLC refuse to sell me an item off of KSL when I showed up with byu gear on. I get comments from children on a regular basis. It's engrained in them from an early age. I have had my car keyed, byu flags torn up, and my license plate cover destroyed all by "a few."
Go ahead and bury your head if you choose to but it's not a small minority. Probably not a majority either but the number isn't small
If you are confident take me up on my challenge in the post you responded to