A wagering requirement priced for slots would be cheap to clear on blackjack, where the house edge is a tenth as large. Contribution tables close that gap: a typical scheme counts slots at 100%, roulette at 20% or less, and blackjack at 10% or zero, so that the expected cost of clearing is broadly the same whatever you play.
The practical consequence runs in one direction: clearing a requirement on a discounted game multiplies the stakes needed, not the cost per stake. Staking 1,000 on a game counted at 10% advances the requirement by 100, so the requirement effectively becomes ten times larger on that game.
Why it matters
The headline multiple of a bonus means nothing without the contribution table next to it. An attractive 10x requirement cleared on a 10% game is a 100x requirement wearing better clothes.
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