Showing Character in Writing

I am reading this book ... A Bitter Harvest ... by Anne Rule. I don't know how someone can write a sentence like 'She liked the guy because her own husband would not replace the kitchen floor' ... I mean the husband in this case was a surgeon. This woman was in a bad marriage etc., but what sort of gets me is how a writer can write a sentence like this without considering the sense of it. I mean does anybody expect a surgeon making a couple hundred grand a year to spend days in the operating room and then one day figure that he will replace the kitchen floor himself ... I mean would you even want your surgeon spending his time repairing a floor? It drives me wild reading books like this. I mean I realize that the book is sort of a representation of fact, but I like books that tell me what the writer thinks, that give me ideas. I want to know why the thing happened. I want the rationale ... the nuts and bolts are okay, but I want to see the whole machine. I want to get inside the thing and take it to pieces. But that's not to say that it isn't a fascinating tale of a psycopath. And it turns out the surgeon is actually an anesthesiologist ... so I guess maybe he could replace a floor ...