It seemed rude to me, too, but I didn't say anything. They were an adult couple with a teenager, so they were old enough to know better.
I've also visited families that have the kids in the same room with us playing video games on the big screen TV while the grownups are chatting.
If anyone comes to my house (hearing or Deaf), I turn off the TV or radio, I don't answer the phone, and I don't use the computer. My guests get my full attention.
