Have you ever had someone copy/compete with your purchases?
I have had several folks copy my purchases and I have copied the purchases of several folks. When somebody finds something good, that works well, is reliable, etc., and like it, of course, then copying is rather pragmatic.
However, one fellow I used to shoot with quite a bit always needed to go further and even went as far as to telling me that he didn't "want me getting ahead of him" or "needing to stay ahead of me." The point to which this really took center stage was in 2009 when we went to a gun show together and I wanted an AR15 of a particular make and model because it had X features. Dang if I didn't find a vendor with them considerably less than I was expecting to pay and so I bought two. Not to be outdone, my buddy who wasn't looking for any just up and bought 3. It was weird.
That was the first time I really took notice because he told me about his issue, and then the issue persisted. The purchases and his need to tell me about outbuying me continued. Finally, I decided he was too weird and don't shoot with him anymore.