Bitcoin's price is determined by 2 aspects:
(1) its utility (normally as a payments network, but other uses too)
(2) its hoarding component (similar to gold)

I agree fees are a good indication of price component (1). The ratio between the (1) and (2) is ultimately measured by monetary velocity. Currently the hoarding aspect is quite a large component of Bitcoin's valuation, similar to gold, so I suspect the fees is a secondary valuation indicator.

FWIW, the mooning of the fees market has been a result of a very recent demand driven fees market emerging since March 2016. I posted this on my Twitter and is part of a larger study I'm doing on the fees market right now.