..... "Someone who just spent $60 to get a silver strike from Silverton's machine isn't likely to immediately sell it for $15.00 either through auction or on a website. And if they aren't under severe financial strain they'll just hold onto the strike hoping to recoup most of their money in a few years."

True; but someone who spent only $4 or $5 and won the same Silverton strike (or more) may be willing to part with theirs for $15.... or if it was purchased from a player who was turning in strikes at the cage. Obviously, patience is a virtue that many collectors have not discovered... or practice.