It’s not considered professional. The uniform is appropriate for combat, not tooling around town.
We had similar regulations back when I was in the Navy in the '90s, though things may have relaxed since then. At sea on a submarine, we wore coveralls (called “poopie suits”). However, whenever we came back to port, the whole crew was required to put on proper uniforms (cotton-based “working uniforms”). The working uniforms could be worn on base, but not out in town. The reason was because they usually looked like crap, with grease stains and so forth. We had a higher class of uniforms (usually polyester- or -wool based) that was allowed off-base. This uniform included your ribbons (i.e. awards), which would never be worn on a working uniform or coveralls.
Since I’m going on about the Navy, I will add that daily life for a submariner consists of:
Training, equipment maintenance, equipment repair, and standing watch (i.e. operating a watch station, including driving the submarine, to manning a sonar panel, to monitoring the reactor back aft, etc.)
We were also supposed to do daily PT (that’s “physical training,” i.e. working out, Tom Tildrum), but it had much less emphasis than for a Marine. PT was the first casualty when workdays exceeded 12 hours. However, if a sailor failed the semiannual physical fitness test, they would likely be ordered to increase their weekly amount of PT.