One of the members here, MightyThor, used an old laundry basket lined with a blanket to take their younger dog places as a puppy. I think he would sit in his 'baby bed" while they ate at outdoor establishments, it could go into a shopping cart at Home Depot or places like that that allow dogs. He wasn't down on the ground walking around in pet stores or around fast food restaurants or other places that might be too germy for an unvaccinated pup. She mentioned that people loved to come to meet the puppy and they'd have little treats people could give to Barley as well.
Another perspective on the scope of socialization for young pups. She socializes but not in quite the same way a lot of people think socialization must be done:
https://www.collared-scholar.com/mor...ze-my-puppies/