It's for wealthy people who have large homes with large open spaces. People who have enough storage that they don't have clutter on the floor.

I grew up next to a neighborhood of 5000sf+ homes, and I never saw clutter in any of them. Some of them had house cleaners, but even the ones that didn't, they had storage everywhere, so everything got put away. A Roomba on every floor would be perfect for them.

I moved away before Roomba existed, but I imagine a lot of them have it.

I have a large home with large open spaces and little clutter on the floor. But I'd need something like 8 Roombas to cover it all because of the changes in levels, doors that are normally closed, etc.

Also, as a semi-wealthy person with a large home, I hire people to clean it including vacuuming, and I don't need an annoying robot roaming the house to do it.

I'm sure there's some correlation between wealth/space and lack of clutter. But my observation is that some people are just much more inclined not to leave a lot of loose things either on floors or table. I'm pretty sure I could have a house that was twice the size and it would still look very lived in.

It's mostly my kitchen/dining room/"mudroom" area that can use regular quick vacs between full housecleanings. But looking right now I have some shoes and other things scattered around and it's literally about 3 minutes to do a touchup with my Dyson stick vac which has been great.