I don’t know that people who identify as Catholics but do not practice the faith are a danger to Catholicism. It is sad though. It certainly looks bad upon The Church to non-Catholics. I think it is terrible that some Catholics do not care to learn anything about the faith either. Not to get too preachy but this thread reminded me of the parable of the Wheat and tares. Incase anyone forgot, this is it from The NKJV
Matthew 13:24-30
24 Another parable He put forth to them, saying: “The kingdom of heaven is like a man who sowed good seed in his field;
25 but while men slept, his enemy came and sowed tares among the wheat and went his way.
26 But when the grain had sprouted and produced a crop, then the tares also appeared.
27 So the servants of the owner came and said to him, ‘Sir, did you not sow good seed in your field? How then does it have tares?’
28 He said to them, ‘An enemy has done this.’ The servants said to him, ‘Do you want us then to go and gather them up?’ ** 29 **But he said, ‘No, lest while you gather up the tares you also uproot the wheat with them.
30 Let both grow together until the harvest, and at the time of harvest I will say to the reapers, “First gather together the tares and bind them in bundles to burn them, but gather the wheat into my barn.”’"
I heard a fairly famous Catholic call The Catholic Church a church of wheat and tares. Then another guy said “Well I am not always the wheat, sometimes I am a tare” And I can relate to that too.

But it makes sense and I will probably think about this parable when I think about why there are so many people in The Church who do not act like Christians.