Yeah there are player that do not get injured...I had a player which did not get injured and played 120 games...
If you manage nicely then you can power train your players without buying greens packs to 6 star...
1 as daily gift you get, and 1 you get when you make a substitution in a match...
So maintain a squad of 22 players then you can play 4,5 friendlies per day...So you can get 6 treatment packs per day and upgrade your stadium form there you can also get treatments...