There were accusations of using a laugh track - recorded laughter added in post-production - so having authentic laughter was a selling point if you’d stumbled across a show coming on after something else.
I’m sure those ones also used laugh tracks, because they didn’t say “Actual audience laughter.”
They'd mix in laughter from earlier takes into later takes. Obviously people are going to laugh more the first time they hear a joke than on the second or third time hearing it. So that seems reasonable to me.
Saying “actual audience laughter” wouldn't mean it isn't a laugh track, ie. actual audience laughter recorded from something else. In the end it's all recorded laughter no matter what they did. So "filmed before a live studio audience" would be the best way to describe it.
Many that were filmed in front of a live audience still had a laugh track. Either to correct them not laughing or not laughing enough at the clearly excellently written jokes, or laughing at things they weren't supposed to was removed or dampened.