What Use Is An F-call?

What use is an F-call? Recently I witnessed something quite amazing. I was at an Amateur Radio club relaxing and chatting with other amateurs. We were scattered throughout the clubhouse, several little groups of interest scattered around. People moving between groups as their interest changed and a whole dynamic ecology of knowledge was being distributed. There were radios set-up all over the place, an Oscilloscope was plugged into a kit to check its operation while the local club shop was open for business with connectors and adapters. It was a real hive of activity, BBQ going in the background and all. While all this was happening, a few amateurs gathered around a set and stopped talking. The radio was tuned to a station that was directing a pile-up. If you're unfamiliar, a pile-up is what happens when one station calls CQ and several stations respond. Then others hear the commotion and they join in, then more hear it and before you know it, there are 20 or 30 stations all on the same frequency, scattered