Yes, Meghan can carry off nearly every choice she makes with ease and grace. I would imagine that her yoga practice since the age of 7, and working out on a regular schedule is what helps provide her with an easy sense of graceful body awareness. In addition, Meghan's actor training and modeling stints would further add to her bodily awareness and knowing how to carry herself with strong yet graceful, erect posture, i.e., walking with shoulders down and back, head high and chin tucked inward rather than jutting out. In addition, dancers and models learn to tuck in their buttocks which helps strengthen one's core and assists in gliding with control and grace.
I've heard that wearing high heels frequently requires excercising one's feet and arches (similar to the excercises ballet dancers do in shaping and strengthening the arches in their feet). It's also having strong leg and thigh muscles that helps in walking in high heels. Plus, Meghan is said to wear a slightly larger size shoe so they are not pinching her feet. And I'm sure she carries flats to slip into on the plane and in cars, etc.