>>115609552 Main Reasons, one objective, the other speculative:
1 (Objective) - Hasbro has a greater target operating profit margin than Bandai, meaning strategically they want their product cost/price ratio to be significantly higher. It's clear that Hasbro focus more on the other 4 P's than on their products.
2) (Speculative) - Bandai is a better run business, either due to having more competitive agreements with manufactures/suppliers, or having a much more efficient operating model.
TLDR; both are completely different companies with different goals, and the quality of the end product is a result of that.