On some older planes you still see the spaces they used to be, but typically they're welded shut so people don't cram them full of chewing gum etc. But modern

On some older planes you still see the spaces they used to be, but typically they're welded shut so people don't cram them full of chewing gum etc. But modern seats have super lightweight liftable armrests that don't even have space for an ashtray. https://thepointsguy.com/news/molon-labe-new-staggered-economy-aircraft-seats/ https://thepointsguy.com/news/molon-labe-new-staggered-econo...