The minion rules are just a formalisation of the rules of thumb most DMs would use to run a big mob of mooks. This is, however, in keeping with the 4E philosophy.
3E philosophy: the rules are a framework for building the world. Where this conflicts with gaming needs, houserule or handwave.
4E philosophy: the rules are a framework for running the game. Where this conflicts with world building needs, houserule or handwave.
If you spend more time running a game than world building, this is a net gain.