A culture founded on the rejection of the sacrament of holy orders can grasp neither the Eucharist nor apostolic governance.
How far, do you suppose, can various camps within Roman Catholicism be described by the sacraments they reject? Here's a rough-draft outline:
Baptism: rejected by indifferentists, who don't much care about anything, and by functional Calvinists, who kick everyone out of the Church they don't like
Confirmation: rejected by pretty much everyone, since almost no one has any idea what it's actually for
Eucharist: rejected, in various ways, by those who reject baptism, confession, and holy orders
Confession: rejected by far too many
Anointing of the Sick: rejected by functional universalists (who needs extreme unction when we're all going to heaven?) and functional materialists (who needs mumbo jumbo priestcraft?)
Holy Orders: the presbyteriate is rejected by women's ordination advocates, who think we can just make this stuff up; the episcopacy is rejected by conservative clerical anti-clericists who understand bishops only in worldly terms as objects of scorn
Matrimony: rejected by arch-Peace'N'Justicers, who think marriage for gays and divorce for everyone are matters of social justice
Since sacramentalism is a sine qua non of Catholicism, I think it might be valuable for someone who knows a lot more about sacramental theology than I do to write something about the harm to their own faith people do by giving in to the temptation to declare that other Catholics -- in particular bishops and priests -- aren't Catholic.