I had trouble with these questions too. The problem for my husband and I is that we have NO real proof of travel for visits. We live in border cities (me near Buffalo, NY and him first near Hamilton, Ontario then Toronto. Never more than 2 hours apart), so we have always driven back and forth to visit. Never have either of us gotten any sort of stamp on our passports or anything like that, and clearly no need for tickets, etc. It felt strange to have to explain all that... My whole life, growing up in a border city, it's always seemed natural to be able to cross the border even for day trips and whatnot (I can, literally, see Canada from the end of my street!)... But I guess with the number of applications they receive from all corners of the world, they kind of have to make the questions as general as possible.