said by wth:More likely there's a crown on the band board and they were too lazy to get a straight one. Around here they use the micro-lams as band board so they're right on.
Is there the possibility that the rim joists were cut because the concrete is not not level, but dips down from the corner?
As far as the bolts go, they require them every four feet here.
They are probably using 2X4s or 2X6s for the sill plate and are easier for the bolt to miss the board. I always use 2X8s. It costs a little more, but when a new house cost $250,000 it's negligible.