Do people in Real Life actually play that Pocky game? [...] For some reason Spin The Bottle is popular in fanfics, but I don't think I've seen an occasion in an anime itself.
I cannot vouch for Japanese, but American teens play all sorts of innuendo themed party games, so the answer is "yes".
Actually, funny he asked. I remember how Ana-sempai went to a slumber party when she was 11, and reportedly girls there spontaneously cosplayed their favourite Bible characters. It's all about the dominant environment. Say, in Oakland they play Russian Roulette at parties.