No I agree...it is actually made from the waste by product of beer... but to me it tastes like a very salty slimy beef extract...and as the link says it became popular with veggies in place of beef extract.
Aye, vegans don't get any vitamin B12 as it's found in animal products, and they don't eat dairy or egg. I used to take some kind of yeast supplement for the short time I was a vegan.
I love salty but not this stuff! I told my husband to pack a jar of marmite when we went to Thailand but he didn't. Fortunately my inlaws from Australia brought tubes of Vegemite for him. He prefers it to Marmite - easier to spread.