Preaching is less a public speaking teaching opportunity and more an act of worship. This means that sometimes, preachers don't tell the truth on purpose. That does not mean that preachers lie, only that preaching as an at of worship is trying to communicate a deeper and transcendent reality than the truth can express. Which is why the old preacher joke ("are you telling the truth or are you preaching?") is funny. Preaching does not always share the truth.
Before we freak out, let me be clear, there is a difference in telling the truth and telling Truth. The story of the "Giving Tree" is not a story about the truth but it is full of Truth. Most children's books I have experienced do not tell the truth on purpose either, but that is to be expected by the reader. I would submit that when we began to see the preaching moment as primarily a "teaching moment" we reduced preaching to teaching the truth and that means many times preacher are not able to express with deep wonder and beauty Truth of the Gospel. Yes, you can make a children's book about how much a mother loves her son and it will be True, but it has not captured the imagination as the story of a tree that loves a boy (which is not the truth but very True).
Many preachers often don't tell the truth on purpose because preachers are not trying to share the truth but they are trying to express Truth - just like Jesus.
The parables of Jesus are not the truth, but they are True. There was not a woman who searched her house for the missing coin or a man who had two sons or a man who sold all they had for treasure in a field or a Good Samaritan or...
If something has to be the truth in order for you to accept any Truth in it, then you are missing a lot of beauty and joy. Don't let the lack of truth keep you from seeing Truth in this world.