And they still do it, what happened at Hillsborough was shameful but no more then what happened at Bradford and yet we hardly ever hear about the fire but Hillsborough is shoved down our throats all the time.
Hillsborough is still with us because of the cover up in the aftermath. Consecuently the aftermath lasted 25 odd years before the new hearing placing the blame where it belonged. Since closure has been so slow in the making, the people involved will need to mark the tragic occasion that was Hillsborough for a long time still. And we should let them.
On another note, all three tragedies mentioned here were preventable and down to football stadiums in the 1980s generally being in a state of disrepair and neglect. Heysel was of course down to the fans attacking other fans, but also the Heysel stadium was old and did not separate the fan groups in a satisfactory manner. When you had an English team versus an Italian at that time, greater measures should have been taken to prevent the scenes that unfolded. In practice, that would mean not playing the final at that stadium.
Bradford City was down to a neglected, old stand and quite possibly insurance fraud. But again that comes down to insuficcient regulations. Practically every stadium had structures that were at least 50 years old at the time. With very few upgrades to stadiums since the 1930s, it will have bad concequences.
Hillsborough happened because a series of events went wrong, which is usually the case when disasters happen. The Leppings Lane stand was badly constructed and was not even certified for use at the time. Add the amateurish and inexperienced policing on the day and the table was set for what unfolded.
There were too few lessons learnt from Heysel and Bradford, and to some extent our own cup semi final at Hillsborough in 81 or 82, where several supporters also were injured. The Taylor report should have been made years before, but it needed a high profile, very visible disaster unfolding before the general public's eyes live on television for action to be taken (my own analysis).
It may not have changed football to the better in all aspects, far from it, but some good came from it. The policing is taking into account that football supporters are people and not animals to be herded with batons (open to debate in some circumstances) and the stadium structures are constructed in a way that fans in general can count on not being burned to death or attacked by angry mobs.