Interesting thought Brian. Let's take it a step further. Humans can also "learn" about pain through discussions like this one. In that light, we can communicate the things that cause us pain (both mental and physical). Add to that the fact that on a 24 hour basis, we can tune into the video medium and see painful things.
"I went to the dentist........." is all we need to hear and we automatically know what the speaker is about to say and we also visualize pain just by hearing the word dentist.
In the wild, we have seen video of predators going after prey. If they go after single prey or the herd, we see the reaction of the prey. I'm sure they are not running to escape a game of "tag". They know what is about to happen.
Why do we question whether fish can sense and/or feel pain is beyond me.