Our standard routine for unloading groceries or anything else for that matter is to open the rear window first to make sure nothing will fall out, then open the huge lift gate. Our old van was a Safari/Astro with the Dutch Doors. That was a great arrangement. Open the full width lift gate, get what you want without anything in the bottom half falling out, then unload the lower half though the 2 smaller lower doors.

I think what makes it common for things to fall out on the EXPY is that the floor is not flat the at the door (or lowered like on MiniVans), so the when the lift gate opens, things that are propped up agains the lift gate fall back and on the ground. I do wish there were some tie anchors on the side walls so a cargo net could be fitted.