Mainly it's just everybody grew up using top-loaders, though it's also easier to get clothes in and out of a top-loader than a front (unless you have a huge machine). [edit]Oh, and also the up-front cost of a top-loader was about $100 less when I last bought a machine.
I've used a front-loader now for years and the only thing I really miss from my top-loader is that I could just leave the lid open for it to dry out. The door of the front-loader is perennially in the way if you leave it wide open, so we have to prop it open to prevent mildew.
I dunno why anyone would want a front loader. If the seal fails, you have water on your floor. If the machine fails during the wash cycle, again, no way to easily get your clothes out without getting water on the floor. If a top loader fails, neither of these things can happen.
One thing I love about top-loaders is that if you’ve found a piece of laundry you forgot, you can just throw it in mid-cycle. Not necessarily ideal but hey.
It works well but takes up more space because you can't stack washer/dryer, in Europe apartments and houses are a bit smaller so if you can save a square meter then that's good.
I once had top-loader in the bathroom of an apartment that I lived in by myself.
Leaving the lid wide open was a pretty great way of living life. I'd shed my clothes to take a shower and just toss them directly into the washing machine. When it came time to start a load it was a simple matter to put some soap in and push start.