"If you don't want it, don't go there" is never enough for these people (either mob).
"If you don't want it, don't go there" does not apply to this situation. The McDonald's in question specifically advertised that they served Halal meat. I agree with everyone here that McD's shouldn't be pandering to the Halal crowd (if you can call less than 1% of the population a "crowd"), but once they started advertising Halal meat, failure to provide it (and substituting non-Halal meat) is false advertising at best, fraud at worst.