I mean good point, but if I'm just using bash as a shell and not writing a script, I'm probably first previewing the contents of a file with cat anyway, and recalling the last command and appending a | grep <pattern> to it is less keystrokes than re-writing the last command into grep <pattern> <file>. Especially if you're playing around with the pattern and trying to get it right, it's nice to have the pattern at the end of the line.

If you're piping any of those commands to or from awk, you can also go.