It seems pretty silly to get all up in arms about copying other peoples' stuff. That's how humanity has innovated throughout the ages: Copy what works and innovate on top of it.

None of our inventions arise from a vacuum. Cars are still as wide as Roman chariots for good reason. Power transfer uses the same base principles as were in play during the dawn of steam engines and before. Energy conversion has been an iterative process for centuries, with the odd leap and bound.

Industrial espionage exists because it works, and everyone does it because it's a cheap way to come up to speed with the leading edge of human knowledge rather than unnecessarily duplicating effort.

Crying "No fair! You stole it!" sounds more like a petulant child than anything else.