its called inflation, you need to take in account of other bands and other tours that span that time from the mid 90's to today... there are probably very few bands/tours of the same stature as SY that have kept the same price levels for the last 15 or so years...
i can think of only think of local hardcore/punk and a few underground shows that still maintain like a $5 cover over that last 15 plus years...
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