haven't seen the OP reply back yet...
I will pipe in though.
Using the picture posted above, from my reading and understanding of the OP, that pic is representative of what he is asking about.
The chrome lining of the carrier from both manufacturers is likely similar in thickness. The interior of the carrier is the critical chrome lined part, the front of the carrier is a non-critical area.
The difference is down to differences in manufacturing. The inside is the important part, the front is overlap... Think of it in a similar manner as "overspray" in painting. One manufacturer's process resulted in more of the chrome sticking to the, non-critical, front of the carrier, than the other manufacturer's process... Like they didn't mask off as much area to protect from overspray.