I actually just learned from a different HN thread yesterday [1] that aliases do get expanded if you add this to your shell's rc file:

    alias watch='watch '

Specifically, if an alias ends with a space, it will cause the subsequent arg to be expanded as well. For example, try running:

    alias beep=echo
    watch beep hello # This will fail
    alias watch='watch '
    watch beep hello # Now it works!

[1]: https://news.ycombinator.com/item?id=31830879