My Macs have drives and we also have an external drive, so not a problem in our household.
Personally, I like the comfort of music, films, programs etc on disk in world where the legitimacy of your ownership might be called into question.
I was only speculating about possible problems downloading the US version based on comments I have seen that the US shop wouldn't export to Canada because of Customs regs. If you down't want to mess around with the UK version on disk, I would give it a try.
I use Reunion which I bought via download.They are an American company based in Pennsylvania.