Great post! You answered my question in the last paragraph. These fees are almost entirely due to the creation, or issuance, of Runes. It would be interesting to see a chart showing the ratio of Runes being issued versus being transferred, or bought. Would exchanging a Rune create the same fee spike as an issuance? 

 I don't see that happening. Unless the seller auctions off the tokens. Since runes are fungible tokens, there will always be other people selling you those tokens without the fee spike.  

 yeah, after its issued in batches, the transfer is quite cheap in terms of vB, its like a normal transaction.