Eric.....All the block layers around just do it that way. Once everything is backfilled, nothing is going to shift. Even my crawl on the house was done the same way by a different block layer. Pinning it, would only reduce any up and down motion anyways, plus you would be going into the core of another block. The footers were pinned to the existing footers though. I forgot to take pics of that.
As far as the top blocks......all of the top blocks are Termite blocks EXCEPT for the one at the man-door, and the blocks between the garage doors. These had to have cored blocks to set the wall anchors so the bottom plate can be bolted. So basically I have only 3-3 1/2 core filled blocks.
The block layer(s) hopefully know what they are doing as the head guy has been doing this all of his life, and he is now in his early 70's. The other has been doing it for about 15 years. When I had the family room on the house done, that block layer had about 30 years doing that type of work, and he put the foundation on the same way. As long as your footers are pinned to existing footers, you should be good.
My existing garage doors.....I cannot reuse them, and you are correct. The new doors are going to be 10' wide, and my existing doors are 9' wide. BUT.....I am going to leave them on. I'm going to purchase a secondary heater for the new addition. That way, I can heat either one side or the other depending on what I am doing on which side, or I can open up the doors and just turn on both furnaces, and heat the complete garage up if I want to. The bumpout will not be heated. I am putting a sliding door on it to keep it clean, but in the winter, I'll probably just leave it open so it stays above freezing as any paints and such will be in the bumpout. My workbench, roller boxes, and overhead cabinets all go into the bumpout. Then I'll just use a cart to throw tools on to bring to whatever I am working on.
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