Rachel: C'mon Daddy, listen to me! It's like, it's like, all of my life, everyone has always told me, 'You're a shoe! You're a shoe, you're a shoe, you're a shoe!'. And today I just stopped and I said, 'What if I don't wanna be a shoe? What if I wanna be a- a purse, y'know? Or a- or a hat! No, I'm not saying I want you to buy me a hat, I'm saying I am a ha- It's a metaphor, Daddy!
Ross: You can see where he'd have trouble
This is from an episode of "Friends". Ross is saying that Rachel's dad would have trouble understanding the metaphor she is using, just as Ross himself presumably doesn't quite get it.
Rachel's parents were greedy. They only understood the value of money. Love was valueless and meaningless to them. They had also married only for money. So, they wanted to marry Rachel to a rich doctor named Barry against Rachel's wish. Rachel told her father on the phone that everyone thought her to be a shoe ; but she didn't want to be a shoe, she wanted to be a hat. She meant that she was willing to be independent in her decision, but unfortunately her father failed to understand the meaning of her metaphor. He said that he would buy her a hat. Ross, therefore, said that if Rachel's father could not understand the meaning of a simple metaphor, he would have trouble to understand her decision not to marry a doctor.