When a friendly associate offers anyone in my household a credit card app, we always say "no, thank you." to which the invariable rsponse is "Well, you never know."
I thought I would mention that a if a customer tells you their credit is bad, it probably IS bad, and asking once is enough. Arguing is just awkward, and not discreet. It hurts their feelings. It makes us embarrassed at our *large* cash purchases.