Perfect Pairs and 21+3 in blackjack, the Tie in baccarat, the proposition bets in the middle of a craps table: all are wagers on side events of the round you are already playing, and all are priced far above the game they sit on. Typical side bet edges run from around 3% to well past 10%, against 0.5% for the blackjack hand and about 1.1% for the baccarat Banker bet underneath them.
The pattern is consistent enough to be a rule of reading: the more a wager deviates from the game's core bet, the more it costs, because side bets are bought for their payouts and their probabilities are rarely inspected. The pages on this site derive several of them, and the derivation is always the same shape: true odds computed, paid odds compared, gap pocketed.
Why it matters
A cheap table can be made expensive with one habit: playing its decorations. Knowing that the side bet is systematically the priciest thing on the felt is one of the most broadly useful facts in casino gambling.
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