The first time I noticed the number 166 was when I was in a grocery store a few years ago. It was in the UPC (Universal Product Code) of Impossible Foods, which offer alternative meat products that are plant based.
Mister Rogers Neighborhood
I ordered three Mister Rogers DVDs, and each DVD has about 30 episodes, but this particular one (Meets New Friends Collection) priced at $16.67 was the only one that had episodes with a 166 in it. Episode 1662 was titled “Love” on the DVD. It ended up being about an Aviary. Wikipedia describes an aviary as a large enclosure for confining birds.