In the last decade or so, it seems to have become more accepted that dinosaurs were closer to birds than reptiles...
So why do they still seem to think dinosaurs had scales or reptilian skin type instead of feathers or fur like kiwis?
"They" don't because they don't really know. When early paleontologists started reconstructing dinosaur fossils, there was not much known about forensic biology. Our understanding of the way bones fit together and the biomechanics of all those little bumps and ridges on the bones was not very complete, and so when the skeletons were reconstructed they ended looking more like lizards than birds, mostly due to the missing information being filled in by the early scientists' prejudices and assumptions.
A lot of the recent work on dinosaurs that asserts their bird-like characteristics (feathers, warm blooded, etc) are inferred from the bone structure and are pretty far-removed from the physical evidence. The notion that dinosaurs are like birds is controversial because it's new, and all people (including scientists) take time to accept something that upsets the conventional wisdom. It is good science and probably correct, but without any direct evidence it is pretty well impossible to know for sure.
However some very-detailed fossils discovered recently in china appear to actually have feathers! So this is pretty exciting and very good evidence for the notion of birdlike dinosaurs. Nevertheless people remain a) reluctant to change their views and b) uninformed about recent developments in paleontology. Most folks in the public are informed by books from their childhood and movies like 'Jurassic park'. The public takes a long time to come around to new discoveries in science, particularly when they challenge older models and when a field is changing rapidly. It is also considered fairly irresponsible to present a controversial and barely-tested theory as "fact" by journalists and museum curators. When the controversy in the scientific community settles down and a consensus is reached, then public education in museums and articles can begin and popular belief will change.