(from the novel)

The small communities on Jakku are all independent, unlike Tatooine were the Hutt mafia controlled everything.

The outpost where Rey sold her stuff was controlled by that alien she sold her things to - he was the only one there with the contacts outside the outpost (including with the First Order) to sell the goods to. The facilities, the material to clean the parts etc. - it all belonged to him (that's why Rey was hurrying, he doesn't like the scavengers to take their time while others are waiting for the spots). He wasn't hiring the scavengers as such, but short of having the means to sell their finds to other distant outposts or villages, they had not much choice but to work for him. Paying them in goods, they couldn't really buy their way out of there either.

In the book he manages to track Rey to Maz's castle and corners her, and Chewie tears off his arm - in a nod to wookies tearing off limbs, and to the cantina. Chewie and Rey then return to the table where Han asks what's going on and Chewie shrugs while Rey says "nothing". Apparently this isn't an addition for the book but a deleted scene from the script, filmed or not.