Suppose I'm an insurance company. If I know how far a robot had to travel to clean your floor, I know your house's square footage which means I can make estimates about your income and lifestyle based on data from millions of other people. Maybe I decide (doesn't matter that it's wrongly as long as I decide it's pertinent) from your probable lifestyle based on this data that you may be at risk for developing a health condition and so I charge you more for health insurance.

If I'm a burglar, it's convenient to map out your house before I burgle you.

There's just no reason pertaining to cleaning floors that the floor plan needs to get saved anywhere. Companies collect data for the purpose of extracting value from it. If they just wanted to make smart devices better, they could have the devices communicate on a closed network without sending data anywhere outside the network.