To be honest, I don't know how this system works, I don't have access to beta.
Are there differences in skill level of these pilots and the cost of hiring them (youtube videos seem to suggest that)? Are they able to train and improve their skills? Are there always pilots available, at every station? If there are stations without pilots available for hire (and it is quite possible, given that you have limited access to ships and modules, sometimes you have to shop around for these), that would be an incentive to keep them employed. If their skills are improving and their skill level makes a difference, then again, it makes sense to keep them employed. It's better to have an Elite fighter pilot than a Harmless fighter pilot. So the question of "pilot storage" becomes the question of how FD envisions the future of this game. If we are all expected to have massive fleets at our disposal (and that's what the game currently encourages or sometimes forces us to do), then module storage or pilot storage probably wouldn't be very high on FD's agenda. If we are supposed to be cosmic outsiders and nomads, with just one or two ships, then module storage, cargo storage and pilot storage is absolutely crucial.
In my opinion many things the Devs are doing are rather contradictory. We buy whole fleets of ships, either to use them to store modules or to perform numerous tasks, each task in a different ship, but at the same time we don't have much influence on the game world. We can't own stations (I'm pretty sure these would be very much within the financial capabilities of many players), we can't take over the existing ones and we are told that FD is not planning any private ownership of the stations. We can't hire wing pilots to fly trade convoys. So this points at FD desire at players being the lone wolf type of a pilot. On the other hand, as lone wolves, we would need tools to make us stick to one preferred ship, such as storage options I mentioned, and Devs are not really seem to be interested in giving us such options. It all seems rather inconsistent to me...