You don't think these folks are wearing safety tipped shoes and cracking dirty jokes from time to time?
Twenty dudes in the middle of nowhere turning trees into a piles of logs are gonna be way more fun to hang around with than a team who's supervisor's supervisor could easily drop by.
Follow some people who work odd hours on Snapchat/IG. Way more screwing around happens on 3rd shift than 2nd or 1st.
IMO the morale boost of allowing people to screw around (relatively speaking) during normal operations offsets the material decrease in productivity because people are more willing to work hard in cases where you need maximum productivity.
The culture needed varies based on the nature of the work.
What works in an office doesn't necessarily work on a jobsite and vise versa. Even then it varies by the nature of the job. The typical "condom full of acetylene" would probably not go over well in a workplace that specializes in something highly regulated.