Revealing mistake: After Johnny leaves, they show Baby standing on the porch of her family's cabin. If you look in the background you see two people waiting for their cue before they start walking. (01:24:30)
Revealing mistake: Knee pads are visible on Johnny during the dance at the end.
Revealing mistake: In the scene when Johnny realises his keys are locked in his car and goes to kick the pole out of the ground there is a light on top of the pole. Where are the wires for the light?
Revealing mistake: When Johnny and Baby are cruising back from their performance in the black 57 Chev, the shift is in "park" position.
Answer: It would be improper to cause a scene, plus Robbie admitted to getting Penny pregnant and insulting her, especially it's what made get an abortion and medical complications.