As an aside :
Low prices of goods.
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One can opt to have a common market without having a union so it's not really a benefit of the EU. Given the right agreements one doesn't even need a common market as such. Not taxing means your home market has less protection. Plus any tax collected goes to governments, which means it need not be collected by other taxes to make up the difference. Overall questionable as a benefit.
Freedom of movement.
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More of a drawback. Less control on who comes into your country. And an ease to undercut the home labour market as folk just wander in from countries with different economies. And for what, a shorter line to go through at the ports ? In any case one can still travel, study, or work in countries outside of hate EU, one simply has to get the necessary approval.
Jobs.
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I'm unsure what these extra jobs are aside from running the EU. Anything we can do connected to the EU we can surely do in the wider world.
Development.
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Paying for others' development is hardly a benefit. And it doesn't need an EU to give one's money away.
Louder voice.
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Even if you believe the world hears the EU's opinion more than that of individual countries, it is unlikely if hears it more than those countries combined. Plus it is clear that a stated EU opinion may not be held by all its members. Plus the loss of our own voice within the EU is too much to pay for it even if it was of use.
Worker protection.
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This seems quite insulting. The claim is clearly that a national government can not protect the workers as they wish anyway. What it means in reality is that the national government's will can/is overridden.
Grants for farmers.
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Not only again is this claiming that the national government could not apply grants where applicable anyway; but out of the EU they'd have more money to do so, if it is thought to be a good thing.
Human rights.
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Even more insulting. Human rights is not an EU owned idea, but it seems ridiculous interpretation of what a human right may be is something imposed upon us these days, so it is another disadvantage. Outside of the EU a national government has to make the definition of a human right for itself, and has no excuse not to do the right thing.