Cliff,
I don't see the issue.
1. Having to plan ahead for use of a cart- Almost everyone who plays at Bandon plans ahead. It's in the middle of nowhere and the tee sheet is usually full months in advance. This is the case at most GB&I clubs as I understand it.
2. Having to take a caddie- This is my exact personal condition. I can only walk the course without causing pain or injury to my knees and/or back by taking a caddie. I can no longer carry or even use a pushcart. The caddies are excellent. A large majority of rounds at Bandon are played with caddies I believe. If I'm concerned about the additional cost or the hassle there are thousands of other golf courses I can play instead, many of them good to excellent, including my club. Bandon has four of the best courses in the world. It's actually a bargain compared to many other high end resorts with famous courses; I don't expect it to be cheap. Furthermore, as stated above, the courses have not been designed for carts beyond the minor turf wear of a few additional carts, around greens, transitions, etc. So to require a caddie who knows exactly where a cart can and can't be driven doesn't seem at all onerous from the point of view of the resort and everyone who values Bandon as it is, without additional signage, paths, additional carts, etc.