Well then, the Catholic Church is in stark opposition to Scripture. There are numerous commands and exhortations to separate from proud evil-doers and heretical teachers who are confirmed in their sin and unrepentant. There is NO PRESCRIPTION FOR BEING "WELCOMING" IN SCRIPTURE.
And there's no prescription for Luther's doctrine of "the Bible alone" either, but that doesn't seem to bother anyone.
Yes, bad company corrupts good morals, but we're all sinners. Which sinners should we welcomed into our Church, and which should be excluded? Unrepentant ones? Sure, but that's a pastoral and prudential judgement. It's hard to tell who's unrepentant, just by looking at them.