That is funny - I had never known it was so pervasive.
I once had a situation where Transferred all of my credit card points to Southwest, which I only booked one-way because I only flew them between PHX and SAN Diego to meet my wife and we would drive the only way home. Every one-way ticket gets screened.
I just called them and said "I didn't opt to get 8 free tickets with just to have to get screened every time I fly with you." They stopped screening me.