Too much $$ for too little

Although I collecto Modern Commemoratives ALMOST exlcusively, I do add interesting and appealing coins to my collection. I have never collected any error coins, but I was toying with the ideal of adding one or two of those smooth edge Washington Dollars to my cache. After looking at eBay and a number of other selling sites, I counted hundreds of error Washingtons for sale, at prices ranging up to $600.00 for the smooth edge ones. That price had increased by a factor of ten in the past few days. In light of the many many numbers of these coins, I decided NOT to buy any. I cannot see that the money spent will ever be "supported" by a rarity of these coins. For those who collect errors, I guess I can see the appeal. Does anyone think, like me, that the asking prices on these pieces will eventually plummet? I would love to hear your thoughts.