Oh, I thought I remembered Roger spanking him, but it was probably off screen. I think David suffers from the ignoring version of negligence and then the reaction when he finally pushes it too far. Let's face it, the lack of attention and love he was raised with could have created a true sociopath (and that was exactly how he started). At least he had his Aunt Elizabeth for some nurturing, though.
Unfortunately, I have enough experience with behavioral problems to say that it wouldn't have mattered if he had been spanked or not. What would have helped is a mother that loved him and didn't leave his life and a father who didn't hate him. When Roger finally did love him, he became more of a brat, rather than the attachment disorder you see early on. How nice that on tv it is so quickly resolved....