I’m not sure Foot is being captured very accurately. Here is SEP:
Among Foot’s most anthologized, celebrated, controversial, and widely cited articles is undoubtedly “Morality as a System of Hypothetical Imperatives” (1972, MSHI). In this article, Foot takes an about-face on the issue of the rationality of morality. In MSHI she retains the view from “Moral Beliefs” that self-interest is rationally required: we must have desires for what is evidently in our self-interest or else we are irrational. Yet, she drops the view that morality coincides with self-interest, and ends up with the position that morality only provides reasons if we have desires that we might rationally lack.
Foot seems to think 1) that moral action is always dependent on our values and that such values cannot be derived from description or ‘is’ statements (whether by “saying” or by “seeing”), and 2) that it is incorrect to hold that everyone has a reason to be moral. For Foot, one’s reasons to be moral are contingent, and therefore they may be absent from some and they may fall away from others.