Такое было только в фильме, если я правильно помню

. Не в книге.
Не, я сначала смотрела фильмы, и там как раз не увидела большой трагедии с нарядом Рона. Ну, кроме того, что в таком стиле никто не был одет, а вот потом читала книги.
He was just piling underwear into his cauldron when Ron made a
loud noise of disgust behind him.
“What is that supposed to be?”
He was holding up something that looked to Harry like a long, maroon velvet dress. It had a
moldy-looking lace frill at the collar and matching lace cuffs.
"Mum, you've given me Ginny's new dress," said Ron, handing it out to her.
"Of course I haven't," said Mrs. Weasley. "That's for you. Dress robes."
"What?" said Ron, looking horror-struck.
"Dress robes!" repeated Mrs. Weasley. "It says on your school list that you're supposed to have dress robes this year. . . robes for formal occasions."
"You've got to be kidding," said Ron in disbelief. "I'm not wearing that, no way."
"Everyone wears them, Ron!" said Mrs. Weasley crossly. "They're all like that! Your father's got some for smart parties!"
"I'll go starkers before I put that on," said Ron stubbornly.
"Don't be so silly," said Mrs. Weasley. "You've got to have dress robes, they're on your list! I got some for Harry too. . . show him, Harry... ."
"I'm never wearing them," Ron was saying stubbornly. "Never."
"Fine," snapped Mrs. Weasley. "Go naked. And, Harry, make sure you get a picture of him. Goodness knows I could do with a laugh."
She left the room, slamming the door behind her. There was a funny spluttering noise from behind them. Pigwidgeon was choking on an overlarge Owl Treat.
"Why is everything I own
rubbish?" said Ron furiously, striding across the room to unstick Pigwidgeon's beak.
Короче, в книгах наряд был старомодным, потрёпанным и затхлым, и это не реакция Рона, а описание глазами Гарри. Причём Молли сама говорит, что от кружев надо избавиться, но в итоге это делает Рон и не совсем аккуратно, а на реакцию сына Молли хлопает дверью и говорит, что если не нравится, то иди голым.

И Падма, кстати, была не в восторге тоже. Не знаю, откуда тут взялась идея, что если она не оскорбила Рона и не убежала, то наряд был ок и она ничего не подметила.
"Hi," said Padma, who was looking just as pretty as Parvati in robes of bright turquoise.
She didn't look too enthusiastic about having Ron as a partner, though;
her dark eyes lingered on the frayed neck and sleeves of his dress robes as she looked him up and down.
Апд. Хотя беру свои слова обратно, подзабыла, насколько нелепо это выглядело в фильме.

Ему и кружева все оставили.