I have 22 players, 2 teams. I have 2 matches everyday and I should train my players at least 2 times in order to improve them and have bounouses for better playing match. all of my 22 players are about 80% condition for each match and as you said, I'm not interested in buying 60 rest packs everyday!
in the other hand, game owners made this game to make money. so we can't say that give us 100 rest pack because we don't want to pay money!
I think maybe gym can give you more rest packs in fewer days because I see my team is tired all the time because I have 2 matches everyday and I do minimum training sessions required, no extra training, no friendly matches, but they are always tired. seems this is the bug of the game. because in normal situation your team is tired and everybody must buy rest packs, still they can play a normal game with no extra pressure on players