Agree with all you say, eohippus. One thing to consider is the likelihood of a broad market sell off (Lord knows we are due). I don't think the low $140 is out of the question. Good point about the World Cup. I had forgotten about that. Not having the Mayweather fight can't help either- although I realize it is only one event.
Simple...they are ETFs and the rules of supply and demand prevail. Buyers come in at $7.50 and support the price. It is COMPLETELY irrelevant as to the "math". You are overthinking this big time. It isn't physical silver. It is an equity (even if it is backed by physical silver). Supply and demand. That is all that matters. How does Tesla sell at over 50% of GMs market cap? Same thing. Everyone knows the math doesn't work and nobody gives a rat's #$%$.