They were probably plain old wild strawberries - especially if you didn’t plant them yourself. I used to pick wild strawberries when I was young… a couple of years ago. Depending upon what type of soil they were growing in and how much water they received seemed to determine their size. Of course I had to fight off the birds to get some. They were very sweet.
When I was in high school I had made a strawberry patch in my our backyard. I planted “Giant Strawberries” (as the advertisement read). They were indeed giant! There was one that was the size of a baseball! I waited and waited for that berry to ripen. One morning I went out to check it before going to school and decided it was time to pick it - when I got home. That day my mother babysat one of my nephews for one of my older brothers. When I got home from school I ran out back to pick that strawberry and it was gone! When I went inside and inquired about it, my mother told me my nephew (2-1/2 years old) had picked it and eaten half of it. She said he did like it very much. I had to settle on strawberries that were only the size of tennis balls to use for strawberry shortcake that evening. The next spring my father told me I had to get rid of the strawberry plants as they were sending runners out all over the lawn. Never did forget watching that one particular strawberry grown though.