Gramps nails it pretty good. The point was to win, place or run as fast as you could squeeze out of yourself on the day. People went out hard and pushed. Most small New England towns that had an annual decent 5-miler would see a winning time in the 24:30 - 25:30 range.
5 miles was the standard race distance in New England in the 70s. A lot of runs, most runs, were in the evenings. It added to the fun, especially in summer, because typically there were beer blasts after.
I recall my pal Billy Gail after winning the Acton 5-miler in 24:00 plus change in 1978, into his cups at the afterparty, telling how he won the race: "I was really hurting so I pretended I was dying and started huffing and puffing. The leader slowed down and I outkicked him". There's genuine old school strategy.
Maybe some winter runs were on weekend mornings but they began at 10 a.m. at the earliest. Once the GBTC started producing good and great marathon runners, some events started happening in the morning. College cross country had become a bit of a big deal around New England then too, with Providence, Northeastern and UMass fielding national-caliber teams with guys running under 23:00 on the 5-mile course in Franklin Park.