As Voris points out, we can't simply throw the bums out. & there are some waiting in the wings to take the place of those who are causing the truble now. But, unlike 40 years ago, this new generation of those attempting to subvert the Catholic Church don't have the pulpit to themselves any more. There is the Catechism that came out about 15 years ago. The Vatican has a website where you can get authentic Catholic teaching. EWTN has a radio & TV presence as well as a website loaded with plenty of authentic Catholic teaching. There are publishers like Ignatius & TAN. & this is only the surface. & there are plenty of bloggers out there.
There will always be those who try to destroy the Church from within. Jesus told us that in the "parable of the wheat & the tares"*. But someday Jesus will return, & at that time He will remove the weeds & only the wheat will be left.
I do have to add 1 other thing. Until that day of death or the return of Jesus, it is possible for even the worst weed (sinner) to become a stalk of wheat through repentance.
* Tares, aka darnel, is a weed that in its early stages looks very much like wheat. Hence the danger of removing wheat with the weeds. But as the wheat & tares mature & ripen their fruit makes the difference clear. (Remember what Jesus said about knowing them by their fruit?) As wheat matures the stalk with the seed grows heavy & droops down. The wheat also turns brown. However the stalk of the tares remains tall & erect, because of how light the seed is. The seed of the tares turns black. Eating the darnel makes a person feel poisoned with drunkenness, & can cause death. Darnel is also parasitic & can kill of the wheat by crowding it out.
OK, I am sure many of you have already caught some depths in this parable you may not have realized before. 1st of all the wheat spike droops because of the heavy seed it bears & the darnel spike remains tall because of light seed. The wheat spikes could be described as bowing down in a humble, worshipful position that we as Catholics are called to have. The darnel stands up like someone filled with pride, like someone who thinks they don't need God or need to submit to His Will or teachings. The wheat seed is heavy, & it is filled with nourishment. That nourishment symbolizes God's teachings & truth. We can also see a Eucharistic connection as the bread used in all Catholic Rites must be wheat. Wheat gives life, physically as well as spiritually. Darnel is light, black seeded & poisonous. That symbolizes the bad fruit born by those who promote false teaching. Those false teachings are light on the truth & they also are poisonous. In this case, the death is eternal death.
There is 1 other interesting aspect about the proud stance of darnel. When harvest comes, those erect stalks make it easy to gather the darnel & throw it into the fire (Hell). Then the farmer is able to go back, gather the wheat & be sure that nothing harmful or evil remains. Those of us who are the wheat will be brought in the barn, a symbol for Heaven.