otherwise our family's seats would be quite scattered around in the cabin. if you know what I mean, usually in a pretty full J cabin (2-2-2) most/all aisle seats are taken first and only single window seats left. and I guess the chance of a baby getting on isn't that big since it's just a few days before departure (not scientific of course, but just my guess).
and not talking about traveling together this time...usually during my individual travel before, when there's no other aisle seats available and only windows left (or even in cases when only the last 1-2 rows are available and I really wanted to be sit more upfront), they usually would very readily offer to put me in the bassinet row themselves (but just always make sure I'm aware that I need to give up the seat if a baby turns up in the end, and I'm always perfectly ok with this rule - but the chance of this happening is just quite low anyway, don't think I have experienced this before, esp in cases like now where all/both of the bassinet seats still available).