Renewing my club membership

I wonder why my brother-in-law keeps buying new golf balls for his training sessions. He's just started on this sport and cant even hold the clubs properly yet. My sis told me his trainer suggested that he practise with those used golf balls instead of new ones. Once he's good at the game, he can use new ones at the club. Talking about the club, i havent been there for ages. Didint even renew my membership. I should take my kids there for a swim one day. But i gotta renew my membership first.