eBay interview questions

Conducted four interviews with eBay. After the initial interview I was asked to provide an analysis of a “hypothetical” new product eBay might offer. I provided my assessment and received feedback that it was well written and thought out. I interviewed with three others over the coming weeks. I did not receive an offer. A few weeks after, they launched the “hypothetical” product, learning through a colleagues LinkedIn post. I felt my product was used to help launch their product and I did not receive compensation for my work. I clearly put a disclaimer on my work that actual use was not permitted. I lost all faith and trust in eBay. Their lack of ethics is disheartening.