If you buy virtually all of it as part of Portfolio, it's a download, and if you buy all the titles separately, they too are downloads, so it seems rather weird if the Bundle in between should be a CD...
Bump!
I agree, it is strange and appears unnecessary. My hope is that ALL resources be available by download someday. I just bought the The Ultimate Archaeology Collection and had to wait on USPS delivery of the CDs. It must still be a relic of the old licensing schema with third party publications.
The curious part is, as you mentioned, you can get bigger and smaller portions by direct download but not the intact collection.