Well, obviously by living in the UK or a European country you benefit from (neo)colonialism and capitalism quite a lot. People here do have a certain responsibility, although more so in making their government and the involved economy take responsibility for their actions. It certainly is a strange position to be in, because you cannot really live ethically under capitalism. But we should still strive to change this, to abolish capitalism and to make the world a better place for everyone to live in. Just seeing that the world is unfair and continuing to exploit people for your own good is imo unethical.

Btw occupation is definitely not only based on military force but more often than not by capitalist exploitation. And occupation doesn't work in a way where you have one distinct group of people conquering some land or people. It rather is the combination of administrative and economic power, i.e. various companies exerting pressure, to maintain control over a people. So yes, if a company is benefitting from the capitalist exploitation of these people and is therefore continuing this exploitation, I would think they are in part responsible for the situation. And it would be unethical to support this domain with your money. Of course, it is a question of degree, because it certainly isn't as bad as directly giving the Taliban money but worse than giving the money to a less problematic country.

It is a bit like paying ExxonMobil, Coca-Cola or Nestlé for a hypothetical service. Do you really want to support them? If you have a choice, use something else. If you don't have a choice, protest against not having it.