To answer your question, yes. There are only a handful of refineries that produce all the gas. It's all pumped into the same pipeline and contains the same epa mandated additives. When it's pulled out by the "name brand", the add some additional additives in order to make it there own blend. At the end of the day, there is no huge difference between them. Just go with the correct octane fuel that your car's manufacturer calls for.
Oh, and use a "." now and then.