Revealing mistake: When Tony goes to the bathroom and scans his blood toxicity, the Tony who faces the camera is supposed to be his reflection in the mirror, but the problem is the reflection is not reversed because it's not a mirror image, note Tony's clothing. Also, note how he scanned his right hand's finger, but then in the "mirror" he's sucking on his left hand's pricked finger. (00:28:30)
Continuity mistake: When Ivan climbs the ladder to inspect the Hammer prototype, his hair changes repeatedly from underneath the frames of his glasses to outside the frames. (00:51:00)
Continuity mistake: In the scene where Whiplash is talking on the phone with Tony, you can see fresh blood running down his hand, but when it goes to the close up of him, the blood is wiped off and there is only a stain. (01:31:00)
Continuity mistake: When Mickey Rourke puts the explosive onto the wall, he slaps it down and it spreads out a bit. We cut to a quick closer shot, and it's suddenly more compacted. (00:43:25)
Continuity mistake: In the opening senate scene, the Senator's jug of water keeps turning around and moving closer/away from the nameplate between shots. (00:11:35)
Visible crew/equipment: When Natalie and Pepper arrive at the Expo and open the car's door a huge lighting screen gets reflected on the door. (01:32:30)
Continuity mistake: After the core is removed from Whiplash during the race scene, a stream of blood visibly trails from the corner of his mouth. The shot changes to him spitting and the blood is gone. The shot changes again and it reappears. (00:37:05)
Continuity mistake: When Ivan is first brought to meet Hammer, Hammer is eating a dessert with a cherry on it. The cherry disappears and then reappears. The spoon also keeps swapping between being inside the food and by the saucer. (00:45:45)
Continuity mistake: When Hammer brings the parrot, the handle above the cage is leaning to the left. A couple shots later it's leaning to the right side, with no one having touched it. (01:04:35)
Answer: He wanted to do something nice for her, but since he is a pretty self-absorbed, shallow multi-billionaire, he forgot about her allergy. He remembered that there was SOMETHING about her and strawberries, but misremembered and thought it meant she really liked them. He makes a simple human mistake, not out of meanness or spite, but because he honestly does not remember.
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