E-marketing specialist Bruno Dillen launched the fundraising campaign after Belgian news organisations published photos showing an orange Peugot 106 turned upside down and set on fire.
Abdeslam "Gharrafi is an electrician who needs his car to work. Let's raise enough money so that Abdeslam and his family can continue to contribute to society," Dillen said on crowdfunding site gofundme.com.
"We cannot allow a minority to destroy lives," he added in his appeal for 2,000 euros.
But the response was overwhelming and more than 15,000 euros ($18,500) had already been raised in eight hours from more than 1,000 contributors, the website said.
So far, more than 19,000 euros ($A27,500) has been donated.
The most surprised was Abdeslam himself.
"I did not know at all. No. What's more, frankly I still don't believe it," he told the newspaper La Derniere.
The mayor of Brussels blamed dockers, hooligans and far-right militants for violent clashes with police during mass protests Thursday against the austerity policies of Belgium's new government.
The troublemakers set fire to 11 vehicles and damaged 60 others, the authorities said, adding around 100 policemen and 43 people were injured.
