A lot of guys, like the older bodybuilder in the last picture actually pump their nipples to get them that big. They don't even have gyno!
Personally, I don't think puffy nipples look bad at all if the chest is really muscular. I think it looks good actually (to give some of those self-conscious guys out there a little relief). There are TONS of people who love prominent nipples.
If someone has a fat/flabby/pseduo gyno chest, thats one thing....but if you are thin or just have puffy nipples, just hit your chest really hard. Everyone says it will "just make things worse," but I don't agree.
What looks better, a flabby chest or a muscular one? I don't care if there is fat or gyno or whatever. Muscle underneath will always look better and more masculine.