Is it normal to make friends this way?

I have had this talk with a few people and am curious what the average opinion on this issue is.

A good friend I have known for years will introduce me to a new person for whatever reason. Over time I will establish a friendship with this new person. Eventually the new friend has issues with the original friend and they no longer communicate. I maintain friends with both friends but the first friend wishes I did not hangout with the person they introduced me to.

I have always thought people make new friends through people their friends introduce them to in order to expand their social network. It becomes awkward when the friends have a conflict.