"You're not afraid to talk to me," Greg pointed out after considering Harry's words for a few minutes. "She wasn't afraid to talk to me." He gestured at the woman, still apparently trying to decide whether a yellow puff or a black one was 'cuter'. No one was afraid to talk to him and he'd made a few sales already, when George had been busy. He might not fully understand yet why his mother had insisted he get a job, let alone a job in Monument or Diagon Alley, but he had done what she told him to do and he wasn't going to muck it up now.
He frowned, dark eyebrows drawing down over his eyes. "Why would I do that?" Then he'd have to find another job. Ron Weasley had been annoying, and Greg so far didn't think much of George but that didn't mean he wanted to sabotage the shop. That just seemed like a waste of energy. He gave up trying to follow Potter's logic, his expression clearing a little. "I needed a job." It really was as simple as that.