1.) don't think about it too much
2.) Since you asked though, I couldn't find a video no matter how hard i tried, but there was a study where they found a bird species recognized the red stripe on the mother's bill from when they were young and so they were attracted to it when they were older. They got a popcicle stick and put a red stripe on it, and the birds came. then they put a thick stripe and compared it to one with multiple stripes, and they went for the multi stripe one. Humans are similar, in your mind you're still seeking the boob, and the bigger they are, the more they demand your attention.
3.) You can't have big breasted characters in western cartoons because breasts are very sexualized in western culture and sex scares people. They are terrified that their sons or even daughters might see a pair and become interested or aroused except they completely forget that they have to eventually if they're gonna have children and that just because sex is acknowledged doesn't mean it is being pushed necessarily.