Thanks to divorce & remarriage, I used to have 8 living people that I considered grandparents, plus a few more that I guess could’ve also been considered grandparents, but they were estranged and I never met them. If everyone is divorced and remarried, I think you could claim up to 16 grandparents!

I have most definitely seen higher effective suggestions at coffee shops. I ordered a single drip coffee (~$2.50) and the suggestions were $1, $2, or $3.