I've experienced the same thing and it's why we don't use cleaners anymore. They frequently banged their vacuum into furniture and down the stairs. They were really hard on our hardwood floors.

You can mention it but I doubt they will change. They might pay closer to attention when you're home.

I also watched the cleaners and realized my husband and I could spend a good hour and a half and get the same result and save $150.

This weekend I was playing with DS on the floor and noticed that the coffee and end table table legs were scratched up. I wasn't sure how this happened as the furniture is relatively new and no one really uses the living room. I looked at the furniture in other rooms and the bottoms were also scratched and in some cases even chipped in spots, including the dining room table and chairs and some of our bedroom furniture. DH mentioned that one day he was here while the cleaning service was here and that they were banging the vacuum into furniture really hard. What would you do? Mention it to them? Get rid of them? Probably if I didn't notice until I was crawling on the floor, others will not, but it seem unacceptable.