Catalogue, it is quite possible that they will not draw down on...

Catalogue,
it is quite possible that they will not draw down on the $150M (some, but not all). If so, however, then the bond holders will still need to have the funds parked away somewhere so that they can be readily accessed anytime in the future. So, whilst I consider your point made (ie: there is no indication of drawing down the full amount), it is also very likely that the facility will comprise two primary costs:
* the coupon rate (so the 8% rate on drawn down funds); and
* a facilities management fee (of sorts) reflecting the opportunity cost requirement of having the facility in place, reserved and the funds assured (could be anything from 1% - 3% depending upon the source of the funds being obtained).

The one thing though that can arguably be assured is that the Bond facility will not be at a nil holding cost to the Company. So, there will be a cost irrespective of the amounts drawn down (if any).