How many do Japanese people really like "Blood Group Talk"? I'm sick of being asked of mine. Some get surprised, some nod saying " Just as I imagined", and so what? It' no wonder. Group A can be seen among over 40% of Japanese.
Frowning at the person who asked me would be childish, and I make it a rule to change the topic, especially when someone told "Mine is group B." I don't believe any Blood Type Personality Advice, but the only thing I can say is Group B blood person is apt to be made fun of by the people present.