The roomba isn't the only possible form of robot vacuum. There may be other options for a design that isn't general purpose but eliminates those issues. Perhaps we should just install elevators or dumb waiters in houses (dumb waiter may be cheaper because it doesn't have to be human rates for safety, while elevators are also useful for humans in wheel chairs which at some point in your life is likely to be someone you are close enough to that you would want to invite them into your house). Likewise doors that can open themself are an option that can solve other problems (think star trek - not current technology)