are you certain the meat was grown 100% animal free (outside of the stem cell line)? As far as I know, higher organism stem cell culture is still not possible without some amount of animal product in the growth medium. For Memphis Meat's burgers last year, for example, fetal bovine serum was used. As far as I looked, they don't make any outward claim of actually being animal-product free (they use cagey terms like "clean", which doesn't have a legal definition, or "from self-reproducing cells"). Fully animal-free meat is a laudable goal, but I wonder if a company that is being evasive about what their current product line is under the pressure of "demoing something, just anything" has the chops to solve the problem of removing all the animal derived products from the growth serum (this is NOT a trivial problem, and some very smart people are working on it because of its arguably less frivolous application towards safe in vitro organ growth for transplantation).

Moreover, an important question is how many replication cycles the animal stem cells use - unless they're hybridized with tumor cells, they will eventually run into the hayflick limit, at which point you'll have kill another animal to obtain more stem cells.