I know my wife likes to tumble dry certain things but clothesline dry other things. Searching through the washer after it's done washing to find the right clothes to pull out is both more prone to error and and no easier than separates.

Of course, that doesn't explain why they don't sell them to bachelors. I can only imagine that it's because it requires a front-load washer, and those are also few and far between in the US. Why that is, I also don't know. Maybe some UL problem?