There are exactly two ways for men to deal with other men. The first is by force, and the second is by reason, which in practice means by voluntary trade. For examples of the first, look at the anarchism of the period after the fall of Rome but before Feudalism ruled Europe, Christian rule after that point, fascist rule, communist rule, Muslim rule, tribal rule, etc.
Observe the social systems proposed by altruists. They first put on the table something which, if it's not "guaranteed" by a proposed social system, they reject it out of hand.
How will it provide for the needy?
They don't ask if man must produce before he consumes. They do not ask if production has any prerequisites. They ask if needy people will be given what's produced first.
Capitalism does ask such questions.
Objectivists do not see Capitalism as something compatible with social conservatism, because things such as drug laws and censorship defy property rights and people's rights to their life. Also, it is not defined with Objectivists as the use of economic capital to expand business, but as a system where individuals have property rights, no matter what they do with it. The concept of economic capital is just the efficient result of lassiez-faire Capitalism.