Because it popped up in my news feed and it was free.
No, unless I get diagnosed with a shortage or deficiency of Amino Acids which is unlikely I can not see the point.
Any person that eats normal food 2-3 times a day will have an abundance of amino acids going around the body, if we needed this crap we would have died out as a species millions of years ago. Our Bodies are quite capable and well adapted to perform at peak performance with the normal foods we eat, no need to micro manage.