Yes, BUT - we did this on a recent trip and although my friend added her card to her band at the front desk (I had added mine online), and she set her own pin, and our other two friends each had cards attached to their own MBs, on the last day I got an invoice showing that all of my friend's MB charges had been charged to my credit card. She had used her own MB and entered her own pin throughout, but it still ended up on my credit card somehow.
We didn't go to them about the snafu because it was just easier to have her pay me the money for her share. But we did have to go through the invoice line-by-line, separate and add up her charges.
So just beware. The system isn't perfect.