I think you may be approaching this from the wrong angle...
The mats are a by-product of doing missions etc, so are 'profit' enough, not a sole source of income...
I get it, but even so I find it a waste of time. Instead of opening every box and camping under every terminal and then rummaging through the bartender menu on my carrier, I'd rather just do something else. I cba to do the math but I'm pretty sure that in the time it takes you to do 100 missions picking up everything from every terminal and container and locker and then going through the bartender menu to sell it, I would be able to do the same 100 missions AND spend half of the time I saved by not scavenging the settlements on a dedicated money-making activity, and in the end I will come up ahead, both on the time spent and on money earned. The prices on on-foot mats are just that bad. Not to mention that I find rummaging through boxes tedious and annoying in the long run and I really would rather just do the mission and then go do something else
That is not to say that I discourage anyone from playing how they want. I get it that there's the OCD factor where it just
feels good to pick stuff up and walk out of the settlement with a phat bag of l00t like Indiana Jones. Fine, you do you. But in terms of the money you can get out of selling mats vs time you spend on just picking them up, it's still a waste of time. The prices you can get are just
that bad, compared to literally anything else that makes money in this game.