Watching the Straw Hats timber the trees and build a giant cart for the dragon makes me think they could make money as a construction crew of sorts. Their assortment of skills is useful for more than just piracy & battle, they are in fact able to do quite a lot of things critical for society to function & prosper. On their adventures, they have more to offer than just fighting. However, this type of lifestyle lacks the glamour & excitement of their current lives, as well as failing to draw their attention thus encouraging the development of the aforementioned skills. That is to say, if the Straw Hats were not focused on improving skills to assist with their impressive goals, they would have never enhanced the ancillary skills that give them such advantages in everyday life.
This sentiment ties into the exchange between Apis, Luffy, & Nami:
Apis: “We’re all gunna die!”
Luffy: “Not if we keep our heads down!” (*immediately hits his head on a tree branch*)
Nami: “Take your own advice!”
Luffy is a fearless pirate who has a natural curiosity. As such, he would almost certainly not “keep his head down” in a literal or proverbial sense, even though he recognizes it as good advice. His gum-gum skills would allow him to easily keep a low profile but it is more his style to just keep his head out looking around, so he does that.
Last note, this is again an even more organized battalion of Marines, section 8, and just Luffy & Sanji alone are able to make very quick work of them. This type of power scaling, in which the Marines are somewhat infinitely more powerful than average people, yet the Straw Hats are somewhat infinitely more powerful than any Marine, creates a skewed sense of hierarchy while setting up for even more powerful threats in the future.