Transnational corporations have introduced consumerism to all parts of the world, leading to serious overconsumption, often through dumping. They have promoted a culture of consuming disposables, and disposing even of durable goods. They have taken advantage of loose pollution laws in less developed countries (look up 'pollution haven hypothesis') and turned numerous locations around the world into rubbish dumps. More developed countries have also been known to dispose of rubbish, particularly poisonous e-waste, in Africa and in cities like the notorious Guiyu in Guangdong, China. Sure, international corporation can speed up the development of environmental technology and foster international corporation to reduce pollution and GHG emissions, but we all know how effective that is - just look at the Copenhagen Accord.
Globalization is good. It allows better communications, standardized parts and currencies, and allows rich people to become even richer by allowing them to expand across the globe.
Detractors cheerfully ignore the fact that globalization allows them to have that imported from wherever whatever that they're used to.
Also, consumerism is good for business, and business generates tax revenue. When was the last time you had a, say, Starbucks coffee? Globalization made the cheap importation of the beans possible, as they cut out the middleman between the bean sellers and their supplies.
Or how about the electronic device that you're perusing this on? Without a globalized Microsoft, IBM, Apple, or [namedrop of some consumer electronics manufacturer], you would have paid a higher price for the same equipment.