When I started running track and cross country in the mid-1980s, a good pair of shoes was a pretty spendy item. I think I spent about $85 a pair back then, usually for Nikes, Asics or New Balance. Using westegg's inflation calculator, I found that translates to about $160 today.
I bought a pair of mid-level Saucony running shoes at Big 5 the other day for about $45, which is usually how much that kind of shoe is at that store. The shoes are at least in the top two of best shoes I've run in, so it isn't that my taste has run to the cheap and shoddy.
Maybe running shoes have replaced gasoline and food in the Consumer Price Index. That'd help explain the phony baloney inflation news we keep hearing.