Some people love the taste on its own, some people really appreciate coffee paired with certain foods, especially desserts. The caffeine might have really helped them get in the habit of drinking coffee, but even if they give up caffeine, or want to drink less caffeine in the evening, they still appreciate the ritual.
I never was a coffee drinker, but I was addicted to caffeine via Coca-cola and I love hot tea with certain cookies. Unfortunately, caffeine free Coke is drastically different tasting than the real thing, but even still, sometimes the carbonation and sugar are close enough to fulfill my craving for Coke with certain foods. Caffeine free tea is just fine.
Coffee drinkers are lucky that decaf is available at almost all restaurants. Caffeine free tea at restaurants is almost always some herbal thing I don’t want, and caffeine free Coke is always diet that I don’t want.