I once saw a quote that said: No matter what you do for your children, when the time comes, they will blame you. As a mother, I try to remember this daily, because somehow it helps me do my best for her. Relationships between parents and children can be very complicated, but I think that if, as parents, we give enough space for love and respect to flow, nothing will be done forcefully, even on these dates. Only accept the gifts, thank them if they feel like showing you how good a father you are. It's difficult not to be able to demonstrate this even when a specific date is required.
Some people seem to think that since they are going to get blamed anyway, they needn't be their best for children. What kind of parenting is that?