No because FAs often reopen them anyway to see if they can fit something in them, or if they can rearrange them to make room for something to avoid it being gate checked. This happens often on the planes I fly (I always fly AA, so can't speak about other airlines, but I would imagine it's common). So I just put my things in and sit. FAs know the best way to move and rearrange. And they always do that final walk-through anyhow, so it's not exactly a lot of extra time to shut a bin.