Well you could just not use any scavengers. The problem is the base yield for scavenging is basically zero. Then you get like a 2-3 merch bonus for 60 int, another 2-3 for 60 survival, and another 2-3 for the actual scavenger trait. So a scavenger who has all 3 gets like 6-9 merch per day while a scavenger without any of them brings back literally nothing. I think Laika and Loden might actually get an extra bonus if they're both scavengers but I'm not sure.I gotta say, I find it so weird that Scavengers get bonuses for intelligence when basically every character that frequently gets the Scavenger Trait is a complete idiot when you get them... I have no interest in sending Loden, Laika, Savant, etc to school for a couple in game years just so they can pick through trash better.
I had a game where all of my actual scavengers were doing something else (mostly studying at the academy to get that intelligence up), and I put like 60 slaves on scavenging duty but none of them had 60 int, none of them had 60 survival, and none of them had the scavenger trait. With 60 scavengers, my merch income was... zero. That's how much the bonuses matter for that.