An aileron roll is a low positive G maneuver that, if done properly, can be done in any aircraft. Since it is all positive G, pouring a drink is easy! This is different from a slow roll, where the wings have a negative angle of attack for part of the roll and you are hanging by the straps. The soda, not having straps, would get a bit messy.
It's also a good idea not to have unsecured objects, such as a soda can, out and about when performing such maneuvers. They could slip out of their position and jam a control - best to give Murphy the benefit of the doubt.