Labeling is an attempt to ban GM products, it is not to educate. Many anti-GMO activists state this explicitly.

You start with a very broad assertion and your justification seems to be a qualified. Many anti-GMO activists may take that position like you say, but that doesn't seem to support the argument that labeling is an attempt to ban.

The decades old scientific consensus is that there is no difference in health or safety between GM and non-GM crops.

There are effects other than the direct health impact of consuming a product. For example, many GMO products are tailored to allow heavy pesticide usage which some people may wish to avoid subsidizing. There are also potential issues with GMO crops escaping containment or with GMO companies like Monsanto's business practices.

There is no compelling reason to mandate a 'life-style label'.

Seems odd that wanting to provide accurate and detailed information about how products are produced and what is in them would be a "life-style" issue. The more information that is available, the better choices an informed consumer can make. Not just about how purchasing the product will affect them personally but about what sort of business and production practices their money is going to go to perpetuating.

Most GM crops are animal feed or are processed to the point that there is nothing "GM" about the product. Maybe you can point to the "GM" part of a sugar molecule. How can such a thing be meaningfully labeled or enforced?

Some cocoa is harvested by child slave labor, some diamonds are produced in a way that funds death and oppression. That cocoa or diamond may be indistinguishable from cocoa or diamonds produced in ethical ways but as an informed and responsible consumer, I would like be aware of the conditions of its production so I can avoid funding warlords and slavers. Does that seem unreasonable to you?

Just to be clear, I am not anti-GMO. I don't think there's anything inherently wrong with genetically modifying stuff.