It sucks for sure, but it's sooo much easier to to hang large quantities of product, in a secre manner, right in front of the customer, who can buy on impulse, without ever to find and wait for a 'team-member' to help them with something.
You guys are all looking at it from the wrong angle. Collectors and efficianados (of all sorts, not just knives) may want the tactile experience, but for mass consumerism, it's perfect for both the retailer and the buyer. For the retailer, it's easy to stock out in the open, secure, workers can quickly identify product for restocking, and it's simple to scan. For the general consumer, it's quick to identify, self serve, can be thrown (literally) in the cart, and easily run through self checkout.
Yeah, it sucks, but then again, the knives you're seeing in clamshells are usually the lower budget ones aimed at the general masses to begin with.