It's all about the neighborhood.
Though, you're probably right. Crack is small amounts for small amounts of money. He'd be better off selling cocaine to higher income individuals. Sell it an eight ball at a time to individuals or scout out groups for Os. It's what, around 70 bucks a gram? He has to move 5100 grams to match his salary. That's fewer than 1500 eight balls. Then it really is about the right neighborhoods, affluent areas of somewhere like Chicago, New York, LA, or even the right places in Seattle or San Fran or something like that. Could probably move it an O at a time, that's 8 eight balls. 182 Os, sell them primarily on Friday and Saturday nights. If he sold two a night he could beat his salary in revenue.
In terms of profit, he'll never make it that way. So, he will need to sell to dealers. Depends on what he pays for pure and what he's cutting with to tell.
Though, if he gets in the position where he can deal to dealers and has a pure hookup, he can make tons more money on crack. It's just low money on the front end.