I think the OP displays a surprising level of naiivety in expressing surprise at acquaintances being hired, let alone that this somehow amounts to nepotism of all thngs.
Recruiting is a hugely time-consuming and tedious business, especially if you are looking to hire numerous people. The recruiter's job is to identify not necesarily the best, but those acceptable to the requirements and also to the company. Given the vast number of applications they will be deluged with the recruiter has to filter the wheat from the chaff, along with a goodly amount of dross before he even has a pool from which to pick the chosen ones. Chewing through say 45 to select 15 would take ages; all have been found suitable, but which to pick? If there are familiar faces in the pile of CVs who are a known quantity and suitably qualified it would be remiss of the recruiter not to fish these out and maybe reduce the pool-trawling exercise down to selecting just 10 candidates as 5 have effectively been self-selected. Everyone benefits, much time (thus money) is saved, the company gets people it knows will fit in and who are a known quantity thus reducing traiing risks. As long as it asn't overdone and an elite cadre develops it's fine,
I submit it's a far superior system to the way Easyjet - and others - used to do it, using pallid clipboard-weilding academics right out of the University of Essex with sociology and "human resources" degrees and zero life-knowlege lording it over career-served ex BA Captains and Military pilots - making them grovel on the floor doing lego bridge-building teamwork exercises, and crossing people off the list immediately if they were foolish enough to have turned up to the ritual humiliation day wearing a tie...(thus demonstrating an unsuitability of character for Easyjet, apparently!). Numerous absolutely top guys fell foul of that awful, horribly prejudiced system.