You know, it's funny you mention this! I was just telling DH that we needed to get one for our trip since we only have one sink. He couldn't imagine why we would need this when we can just keep all of our stuff in a suitcase. I tried to explain to him that we can put out contact solution, shaving cream, my face soap, toner & moisturizer, meds, sunscreen and all kinds of stuff in there.
He'll thank me when we get there and he realizes that it's much more convenient than digging through a suitcase all the time. He doesn't have to use it if he doesn't want to, but at least all my crap will be organized!