Safe Standing at todays Chelsea game
Stadiums have been all seater since the Hillsborough disaster of 1989. This was just an excuse to introduce seating at top level stadiums, as the real reason for the disaster was the perimeter fencing preventing dispersal onto the pitch. And some blame also lies with the police and some supporters.
The real reason seating at football stadiums was introduced was purely financial. Football club owners realised they could charge a lot more for a seat than for a standing space. Back in 1990 a ticket to stand at a First Division game cost about £2, when seating was introduced that ticket rose to £20.