Ubuntu and debian work exactly the same when you need a password. The difference is when you use debian you type the root password. When you use ubuntu you type your own, personal password. It's really not that big of a deal. There are people who think sudo is the worst thing that ever happened to linux but on a practical level it's not that bad of an idea, at least for a personal computer. Certainly if you're running a dedicated server you don't want sudo but I think most people understand this anyway.

FYI you can create a root account on ubuntu and disable root / install sudo on debian.