Golfer’s memories are similar to my experience growing up and as a young married. Nobody sent store bought or packaged items except if there was a bottle of alcohol.
In 1990 I was shul president. The rabbi and I discussed the problem of receiving home baked items that we might not reliably eat. We got together with the president of the sisterhood and came up with a new program.
The Sundy 7-10 days before Purim was baking day at the shul Members brought in their ingredients and they were all checked and approved (or not) by the rabbi. All mixing was done with shul utensils in shul keilim. Baking was done on the shul’s sheet pans or disposable aluminum trays. After teh items were cooled each person would package tehm in polyfilm tape or tie them shut and a sticker would be affixed stating that these homemade goodies were made under the personal supervision of Rabbi xxxx and were Pas Yisroel and pareve or cholav Yisroel as marked.
We charge $18 per baker which went to the Matonos Evyonim Fund.
This system worked well for about 10 years until the shul building was sold. The new building did not have dairy ovens.
My BIL was a shul rav in Massachusetts and adoped this idea and it has been in place fopr 25 years.