There is an old Vegas poker adage that goes like this. When you sit down at the table and can’t figure out who the sucker is, then it’s probably you.
In horse racing, gamblers use the term “recreational money” to classify novices who typically bet a lot of “dead” money into the pari-mutuel pools. It’s one reason why veteran horseplayers look forward to Kentucky Derby day. The betting pools are huge and buoyed by dead money from novices that makes those payoffs overly generous.