Kantian 'imperfect duties' (unvollkommenen Pflichtcome) come to mind. We have an imperfect duty of beneficence. This means that we have an absolute duty to help others - no rational agent could prefer a world in which nobody helped anyone else since this would be most likely self-harming. But that does not mean that I must e.g. donate to every charity that asks for money. I have a choice, from the unlimited range of possible charitable actions, of which specific charitable actions I will do. So I give money to African famine relief but not to Syrian refugee camps. Or I give to both of these but not to Homes for Retired Actors.
There is nothing glib or arbitrary about my choice. I make it conscientiously in light of what I know about the level of need, the reliability of the charity and so forth. But the point holds good : giving to one charity or to a number of charities absolves me from a duty to give to others. I have finite resources after all and other proper demands on my income.
For Kant on imperfect duties see Kant, Metaphysics of Morals, II Metaphysical Principles of the Doctrine of Virtue', §VII. (Kant: The Metaphysics of Morals (Cambridge Texts in the History of Philosophy)
Kant: The Metaphysics of Morals (Cambridge Texts in the History of Philosophy), Editor-Mary J. Gregor; Introduction-Roger J. Sullivan.
ISBN 10: 0521566738 / ISBN 13: 9780521566735
Published by Cambridge University Press, 1996: pp.153ff; note also p.32.