I have seen that happen a number of times and it bothers me too, especially when the priest doesn’t make any effort to make sure those waiting in line for most of a half hour or an hour get a chance to make their (usually much shorter) confessions. Some priests will come out and say, “I have to get ready for Mass now but will hear confessions afterwards” in that situation.
I know that perhaps the priest really needed to spend the time with the person, but in that case some accommodation needs to be made for others who are waiting. A couple times when no such accommodation was made, I ended up having to drive a half hour to some other church with a later confession time in order to get my confession done, as I did not want to wait a whole week for the next scheduled parish confession hour.
