Yes, some women are just "bigger" than others, including bone structure. That doesn't keep them from being attractive, such as the girl in your links. Even bigger girls than her can be attractive as long as they're shapely. For the most part, an attractive shape means having a defined waist (smaller than chest or hips) and a *relatively* flat stomach (it doesn't have to be tight as a drum, or have "abs", but you don't want a big belly bump or fat rolls).
None of these girls are "skinny", and I'd bet they are all above 150 pounds, but they don't have any stomach or arm fat, no fat rolls, and they have waists. They also have hips and boobs; in other words, they are the definition of "curvy." The fact that they aren't tiny thin women doesn't make them any less attractive, except to a small percentage of guys who ONLY like stick-thin women. The vast majority of guys would find any of these girls to be attractive and sexy (they may be a little too old for most of the crowd here, which are HS/college-age, but still).