GM Crops. Why??

A multi generational study of mice conducted in Austria appears to have reignited the debate as to whether GM crops cause long term changes in fertility and the health of offspring. The report (which can be read in full Here) was commissioned to discover whether there were any statistically significant changes over several generations of mice when the control group were fed non GM crops and the test group had a diet that included 33% GM modified maize. From the report it appears that this was much less a "Force Feed" regime, it was much more a "we'll let the mice live a normal life" if life can be normal in a lab.

The important part is that there were differences in litter size and offspring size, with smaller litters and lower birth weights.

Now the important question. Why do we need GM crops? I've heard people say that if we don't have them we will not be able to feed the number of people on the planet. Perhaps having LESS people on the planet wouldn't be a bad idea. The other point I've heard made is that we would "return" to much more labour intensive methods of weed control. So what if we do? Even in my area, rural North Norfolk, I've seen crops for the last 20 years grown without any GM manipulation increase yields thanks to better husbandry.

The driving force for GM is money, certain companies see it as a way that they can make large amounts of money, and when there was, at some point an idea of introducing a "Sterility Gene", producing a crop that cannot be used as seed is totally unethical. We have farmers everywhere having, for countless generations, using their harvest as their seed for the following year. These companies, if they have their way, would stop that dead in it's tracks -- literally. After the harvest, you want to grow something, you BUY new seed. Who provides that? They do!! And as a result they make more money. What happens if you don't buy seed, whether GM or not, you cannot grow anything.

I only have one question, where are the ethics in this?