Jack once nearly fell of Arcee after a ko burger shifts and a long school day, since then Optimus picks Jack up. Optimus doesn't show it but it makes him happy that he gets to spend time with Jack. So when he picks him up, Jack often falls asleep. Optimus knows that and purposefully drives a longer way to the base.
Once Miko fell sick and Bulkhead was on a space mission with Wheeljack. Miko didn't want to rest so Optimus offered to carry her around, which she accepted. He didn't put her down even after she fell asleep and did all of his work with one servo.
When it gets to loud in the base or Miko gets to wild, Optimus let's Raf study and read in his personal hab suite.
Jack sees Optimus as his father figure and unintentionally calles him dad whenever he falls asleep in Optimuses cab.
Miko came up with the nickname Papa Prime which ended with her once accidentally calling Optimus "Papa" instead of "Prime".
Raf made a father's day present together with Bumblebee and gifted it to Optimus. It was a photo album of the autobots and humans with a handwritten letter.
I love that in the TFP episode Nemesis Prime, the first thing Fowler did while the Autobots were aiming their weapons at Optimus, was protecting the kids in case Optimus did turn evil.
Guys, what if the TFP verse didn't have grocery stores and supermarkets?!
If the Cybertronian diet is limited to liquid from crystal Energon, then they would be completely used to a great beast of a combination between Home Depot, IKEA, and Kay Jewelers. Like a build your own customizable personal fuel station or for the department. Maybe there's minor cultivation of different kinds of crystals that act as herbs and spices equivalent. Look at the displays of crystal decor. While it's Energon, the structures are too unstable or deemed unusable for consumption to be sold (different story for the lowest castes trapped in poverty though)
The 'bots are familiar with a job site providing room and board as well as picking up prepared food from restaurants at different price points. But if Team Prime actually looked into the history of agriculture on Earth, the immense scale and absolute variety would shock them speechless. Optimus would fall into a deep tunnel of botanical science versus the culinary arts and how a lot of veggies are basically the same plant that's been curated to enhance very specific features.
There's a new game at the base and road, it's called "Can you eat this?"
(This actually starts a lot of "lively discussions" between the kids because of cultural differences, family histories, and geographic/regional dishes and traditons.)
And if the kids ever needed to do a report on animals or plants or food, then they would receive full marks.
If the 'bots ever get enough fuel to use a holomatter, then the kids would get the delight of seeing:
Teaching Optimus how to select a good watermelon. The man is in deep concentration as he eyes for a "sun spot, a creamy other side, and a good-sounding thump."
June and Ratchet having a hissy and very heated argument over what's inside the shopping cart. The cart fills and empties between them.
Arcee staring down the produce that is and isn't organic, and then trying to figure out the difference between oranges and grapefruits without breaking them open
Bumblebee buzzing around the honey products and sweets to make puns and jokes. He's having a blast in the personal care aisles, especially with the masks and Burt's Bees.
Bulkhead is entranced by the inside Starbucks and the meat department. He's watching the baristas and counter workers deftly move to produce a new thing. He wants to learn to make a sandwich and a Frappuccino for Miko.