A: The short answer is no.
A: I didn't actually start rolling my dough till the last couple years. Before that I just flattened, shaped and stretched it with my hands and pinched closed in what I called a "6 petal flower". That works absolutely, positively 100% fine. Did it that way for years with no problems. I really just never took the time to roll them because I thought it was just another step I didn't want to do because I just wanted to get them wrapped steamed and in my tummy.
But, once I started rolling I discovered why this could actually be better. Once I got the technique figured it out it was actually very quick. And having the middle a bit thicker than the edges gave the end bao a better structure and rolling helped prevent thinner spots.
So...you can certainly choose the method that works best for you. There are NO rules on how to wrap. Only thing to keep in mind for sure is to wrap different fillings with different "designs" so you can distinguish which have the same fillings.
Komen