Like most slogans... it depends.

I agree in principle, but you are ignoring something crucial called context. There is a real-world situation around it all, with all the karmic consequences that implies, and pretending that actions don't have consequences (in the context of karmic imprints and the web of causality) is assuming a priori a pureness in the whole situation/causality web that just isn't there.

Or in plain English: you can't ignore what others do in a distorted environment out of ideological purity, when consequences are real and your people will suffer for it.

Sometimes you just have to play along, at least for awhile.