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I completely get not dealing with a company with policies you don't approve of, but unless it is a moral objection, it is a trivial one to bypass with technology.
No pre-teen pregnancies in my family that I know of.
My mother was 30 when she had me (I'm not the eldest) and her mother was 28 (when she had my mother). Now her mother was 19 (when she had my grandmother, married at 18), but an average of over 25 years old for birth and my great-grandmother was alive when I was 19 (briefly, she passed that year). My eldest is 11 and my grandmother is still alive (I was 28 when she was born, increasing the average to almost 29).
TL;DR Lots of people know their great-grand parents without pre-teen pregnancies.
Oh, and yeah, my grandparents / great grandparents (only one of mine passed before I knew them) would never drop by unannounced. Heh, my father's father wouldn't even let the phone ring more than 3 times, thinking if you couldn't answer it that fast you were busy & he didn't want to intrude.