To be honest, I'm a little surprised that people predict a huge number of yellow cards in the
free betting contest ... 20+ cards in 4 games, seriously? While you guys may know something that I don't know, even my 12-cards prediction seems a bit exaggerated to me,
[I understand that this tournament is more dynamic, but still].
south americans get a
little more aggressive during international games

it's extremely unlikely that a match over there finishes without a single player getting booked, something very, very likely to happen in the Euro for example. It's like part of the football culture in south america, intense, fierce and aggressive football
check out the cards stats in the Copa America 2019
here, TL;DR: an avg of 5 cards per game
you can even check the
total booking odds in your favorite bookie. No way you'll find good value in under 2.5/over 1.5 cards, pretty much everyone expects a bloodbath
(not literally, you know what i mean lol)