>>49413632you can only use bottle caps on level 100 mons, you get plenty of grit items during the game
IVs have a range of 0 to 31, these have a range of 0 to 10 and only range from 0 to 3 in the wild
You can easily max out your grit during a playthrough, in most games you don't even get access to bottle caps before the postgame.