DEWCs do not have a specific orientation to worry about. You just load and go.
Simple. Easy. Bang.
HBWCs do have a specific orientation that you must pay attention to (whether loaded as a hollow base, or a hollow point).
But they have two theoretical advantages in HB form:
1. The base should expand to fit the bore of whatever they're fired in. As long as the 'nose' diameter is close enough to groove diameter, this is a theoretical accuracy advantage and doesn't require bullet sizing trial and error.
2. The hollow base causes a forward center of gravity, while leaving the center of pressure in the same place it would be on a cylinder of lead (like a badminton shuttlecock). This makes the projectile more aerodynamically stable - another theoretical accuracy advantage.
In HP form, you lose the above potential advantages, but end up with a honkin' hollow point. Or, as one of our members likes to call them, "Turtle Busters."
They could (and likely have), made bullet molds for hollow base, but it is likely viewed by home casters as an unnecessary feature.
HB molds have been done. Many times. I have several - one of which is a regular production item at NOE.
A hollow base is far from an unnecessary feature when a hollow base is what you want.
"Them there hollow pointed bullets are fantastic. But the hollow point part seems unnecessary."