"Yes I'm confused also as if it is sugar from vegetables how can it not be vegan."
Because if the lactic acid starter culture that's used to ferment the vegetable sugars isn't vegan, (one strain is made from whey, whey comes from cheese) then Sodium Lactate isn't vegan. The vegans seem as confused as we non-vegans are.

They may just be looking at whether SL is made from dairy or vegetables, not knowing about the fermentation process. I'm still looking into this because I'd like to know too.
Repeating:
"I looked into it SL a bit last fall, not from a vegan standpoint because I was using it in non-gelled goat milk soap at the time, but here's an article about it.
http://www.sodium-lactate.com/excerpt:
"Sodium lactate is produced by the natural fermentation of the sugars from corn or beets.These sugars are fermented with lactic acid starter culture, similar to those used for cheese or yogurt production. The fermented solution is mixed with caustic soda (same used in pretzel and bagel manufacturing to coat the outside) to form sodium lactate in the same fashion soy milk is mixed with Calcium Sulfate to form tofu."
So the next question in my mind is: Is lactic acid starter culture vegan?