The only was this will be stopped is for all the players of both teams to walk off the pitch and refuse to play, if the players stick together the authorities will have to act.If during the game, Lukaku simply decided he'd had enough and walked off, you reckon the opposing team and it's fans would be fined/banned or Lukaku?
I do wonder if the club are speaking to him off the pitch, telling him to just ignore it and it will be dealt with "upstairs", to appease him.
The abuse Kean got was vile, as is this to Lukaku.
If he does say enough is enough, then I hope black players on the opposing team, walk off in solidarity too.
But the worry in Italy and many other , especially eastern Europe nations is racism is endemic , even in the team itself.