things that have confused me

Now I absolutely love this movie, from the score to the performances, but there have been a few things that have confused me. I get how the people changed, experiencing something new, but how did inanimate objects change, such as the car or the cars etc or the book. Also wouldn't the art book be out of place as it came from outside of Pleasantville? Indeed if the books needed to be explained to change wouldn't then there still be some blank as david could not have read them all. Furthermore why did no one question david when he (as Bud) says where he used to live, Isn't is assumed that he lived his whole in Pleasantville. Finally why did Betty simply accept who David said who he was? No questions asked just that he was a visitor who was going to leave but without Jennifer, who was technically still Mary Sue. I get that when Bud and Mary Sue were replaced by David and Jennifer no one would say anything as often that happens in TV shows actors being replaced bu the other stuff confuses me.