French people and their fidelity card

In the land of infidelity (in their defence, I think everywhere is a land of infidelity, but here in France, people just do it more openly) , French people call their member card “carte de fidêlité”, as if they wish by doing so, it will make them more faithful and more accountable. What is the subtle difference between loyalty and fidelity you might ask, well, according to Cambridge Dictionary online: loyalty is "your feelings of support or duty towards someone or something; while fidelity means honest or lasting support, or loyalty, especially to a sexual partner, so you can see how important French people value member card, they see companies as their sexual partner, it’s fidelity on the line after all…but maybe that explains why fidelity doesn’t really mean a lot to most of them?? Coz who would feel guilty shopping at Carrefour when you have a member card from Monoprix, right?

I remember one time I went to the cinema, when I proceeded to the confectionery counter for some popcorn, the male staff asked me if I have a “carte de fidêlité”, being a first time customer, I said Non, it might seem rude, but when could I do, oui & non are the best words I can utter, he should thank me for understanding him in the first place, and then he continued by saying, “Of coz, who cares about fidélité these days anyway” (God, what did his wife do?) and grinned as if he can see right through I am some sort of a cheater too. “Tout à fait, on s’en fout!” (Indeed, we don’t care!) and then we both laughed out loud. I was actually quite please with myself that I understood what he was saying, so I letted go of his depressing comment about the relation ships.