Whenever I see contrary graphics on vehicle back windows, it tells me to what they prescribe. I have a Calvin kneeling beneath the Cross on my Ford Ranger. I am in Roman Catholic Youth Ministry.
What we present is to what we aspire. If "Calvin" is portrayed in a defiant act, it relates to the owner's contempt of a product he/she did not purchase in a vehicle, or says something about their view of the dignity of humankind. To them, it's marketing in an infantile way. My Calvin sticker that show's what a young child should be doing, is a counter to show what my youth ministry should be.
When I asked an sales attendant at a religious book and gift store if she had such a sticker, she was offended because of her attention to what she has seen on truck rear windows. We should discount crudeness on vehicles and rather portray what is important to what we cherish, especially as it relates to our tradition in Faith, reliant on Christ's suffering and salvation the Holy Cross represents.
My Calvin kneeling beneath the Cross is portrayed next to my Knights of Columbus sticker and my "Im Proud of My 2 Eagle Scouts" on my rear bumper. Just my thoughts!