Vegetarians are pretty diverse and really can't be considered as a single group. Some vegetarians eat fish, some sneak pepperoni pizza, some eat dairy, some will eat anything but steak, some extend the definition beyond food to clothing and furniture. The addition of test tube meat will just add one more variable to further diversify people under the "the vegetarians" label.
In a similar vein, would someone who identifies as Jewish or a Muslim eat test tube bacon? Well, some already eat real pork and don't get worked up about it. It just depends on how you interpret and practice your beliefs. And we've all got different beliefs that make us do different things.
He said "but steak". There are various kinds of vegetarians as he says, some who have eggs, some who have milk products etc. Regarding fish, I actually have relatives from Kerala, South India who are vegetarians who eat fish. They call it "the vegetable of the sea".
In a similar vein, would someone who identifies as Jewish or a Muslim eat test tube bacon? Well, some already eat real pork and don't get worked up about it. It just depends on how you interpret and practice your beliefs. And we've all got different beliefs that make us do different things.