A lot of ppl say its stupid to think that we can play with the buddy pass without buying the real game, but SE make a lot of money on the Monthly payment so it wouldn't be so weird that you could play without the game...
So Sadris, I dont have a real link for the answers, but i emailed Square Enix support to know if my husband could continue to play with the buddy pass or if he really needed to buy a real version of the game, and there is there respond :
Regarding your request for account support. Please find your answer below.
Thank you for your interest in FINAL FANTASY XIV!
Please keep in mind that once the 30-day Buddy Pass offer expires you will need to purchase a copy of FINAL FANTASY XIV in order to continue your adventures. If you do not purchase a copy of FINAL FANTASY XIV after the Buddy Pass expires, the account will not longer be active.
Thank you for contacting the SQUARE ENIX Support Center.