The last team I was in always wanted to publish open access, but only the Wellcome Trust funded person had a specific budget to pay for it. So we either crammed him on the author list and pretended he contributed significantly (unethical all round) or went non-OA (not what we wanted either).
And this is before we get into whose government paid for what. I was US-funded and working at a British university alongside EU & charity funded researchers. Who has the right to see what? And what if the work was partially funded by a company? Or do you argue that all Europeans have the right to read US-funded work and vice versa? I personally would, but I think many people would disagree if I'd written China instead of the EU.
Also, though I think many people will disagree with this, I'm not sure open access - while ideologically preferable - is a panacea for much at all. I've been publishing OA for >10 years, but in practice it makes virtually no difference to accessibility for professional western researchers. Research papers are perhaps best understood and used as professional communications on method rather than descriptions of truth or the state of the art (as a side note I believe this conflict is where many of the arguments over the quality of the literature arise)*. Professional researchers have access to all the papers they need.
OA really really helps researchers in poor countries. And this is the strongest argument for it, where the impact can really be felt and measured, but this is almost never the argument I see put forward by the tech/gadget communities.