Suppose supply for a good is elastic (not perfectly elastic nor perfectly inelastic), and demand is perfectly elastic. The equilibrium price will be some non-zero price. But the consumer gains 0 surplus for each purchase. So do any items actually get purchased at that price?
I think I might have an answer: If you take a regular elastic demand and supply curve, consumer surplus for each incremental quantity is reduced until the equilibrium point BUT there is still a purchase at this equilibrium quantity. It’s the same thing with perfectly elastic demand. Consumers will still buy goods UP TO AND INCLUDING the price at equilibrium that provides no consumer surplus, which pertains to your example. If the price of the good increased the smallest amount, there will be negative consumer surplus and no purchases.
yes, for a perfectly elastic demand, marginal benefit = market price
Thanks, makes sense.