I can't speak for others. I use my brain, and such common sense as I have obtained one way or another.
Because common sense is what lead to discoveries like heliocentric solar system and the explanation of orbital dynamics.
When a story is internally inconsistent, I reject it. Same happens when it includes special pleading or other fallacies.
"Dinosaurs evolved into a 'primitive bird', which was the ancestor of all birds at a time when 'modern birds' already existed." That's an internally inconsistent story. I don't think anyone can actually believe it on their own. Those who make a large enough effort may receive divine assistance.
Enter special pleading: "The 'primitive bird' had actually been around longer - it just doesn't turn up in the fossils". On the principle that things can exist without leaving fossils, the whole evostory can be discarded if one so chooses. Or is there some rule that special pleading is valid in emergency situations to salvage failing faith?
Since you claim that things cannot exist without leaving fossils, perhaps you could show me the bunny fossils in the Cambrian deposits. Humans and dinosaurs lived at the same time? OK, why are the human fossils and dinosaur fossils never in the same layer of deposits and the dinosaurs are always in older deposits?
We have at least a couple of threads already. I'm thinking most of this ground's been covered. Every evolutionist dreams of the day when they'll find a "transitional" series. If one is ever found, they won't need to quibble over what "transitional" or "intermediate" means any longer.
Why would there be no quibble? What incredible form would these transitionals have that would make a firm anti-evolutionist say, "Of course, it's obvious!".