The 'haters' are getting to Opie. You could hear it in his voice. Especially when Bobo's mom got on the line. Opie tried to keep going with his fake-positive personality bit, but his anger was transparent. Jim and Sam were only egging it on so they could witness Opie's insecurity battle the opinions of a retard and his mom. Kind of like how Jim once said he likes egging on angry taxi drivers. Opie has now become the angry taxi driver. That's all.