Lyle’s anger at Eli seems to stem from his desire to protect Eli’s innocence: he perhaps doesn’t want Eli knowing he deals heroin. Bich, on the other hand, has no issue with children knowing what the adults who care for them are up to (this is perhaps why Darren is so well-versed in the local drug trade). Again, it’s clear that Eli idolizes Lyle, when he mentions that Lyle was the one who taught him to be loyal. Bich tries to convey that Lyle is just as loyal to Eli when she insists Lyle deals
for Eli. This suggests that Lyle is trying to help his family by making money in this way.