Keno

Keno is the most expensive game in most casinos, and it is not close. Typical house edge runs 25% to 30%, against 0.5% for blackjack and 1.4% for the craps pass line. A dollar wagered on keno costs roughly fifty times what a dollar wagered on blackjack costs.

This is not a secret and not an accusation of anything improper — it is just how the pay tables are built. The probabilities are exactly calculable, the payouts are printed, and the gap between them is large.

What keno buys for that price is a slow, low-attention game where a small stake can return a large multiple. That is a legitimate thing to want. It is worth knowing what it costs.