McD not only has almost 100k employees it also has over 95% of its supply chain from domestic (Russian) sources. McD is irreplaceable, any other fast food business already have their supplier and not even retail supermarkets won’t be able to absorb the influx of foodstuff, not to mention settle in multi-year contracts.

The ripple effect might put ~500k out of the workforce!

And this before considering the symbolism of McD having opened in Moscow in 1990!