They may or may not have bought it, but the calculations of "lost sales" assume that 100% of them would have bought it at full price, which is absurd. I'd wager it is closer to 10%.
In my lifetime I've easily bought 100x more books used than new, which (from their perspective) is economically indistinguishable from piracy. Any of those "lost sales" estimates strike me as entirely bogus.
