Once a course is done and WGT has recouped its costs from the first several thousand players, it makes a healthy marginal profit from each additional player who tees off.

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It can generate some marginal gross profit, thus making the medicine slightly cheaper for all, and it makes the world healthier all around, too.

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Marginal cost begins to exceed average cost, creating a profit margin despite competitive pressure to price to marginal cost.

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This contributes no profit on the first visit unless the marginal cost is very small or the discounted product pulls through other profitable sales.

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The company should already be charging the most it can for that marginal phone call and a change in sunk costs might affect accounting profit but not that revenue maximising price charged.

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