To ban or not?

Recently there had been some issues involving the defamed Global Ikhwan group of companies, named after the former group Al-Arqam. The issue surfaced after some of its members were arrested suspected on trying to revive the entity into its former state,which were already being banned by the Malaysian Government on 21 October 1994. Founded by Ashaari Mohamed, who had claimed himself to possessed supernatural power from God, he began the movement in the early 70's by a small halaqah at KL and since then, had been expanding his influence all over the country. Ashaari was addressed as Syeikh Abuya in the later years, self-proclaiming himself as the descendant of prophet Muhammad through the Bani Tamin tribe. So what's all the ruckus about?

• Global Ikhwan runs business all over the world, stretching far from Europe to Indonesia. 
• Its activities includes retail outlets such as mini markets, groceries, book shops, etc
• They claimed that they practiced businesses according to the Islamic principles, free from riba and frauds. 
• Its assets amounted to millions of ringgit. They even operated in the field of agriculture and advanced technology
• It was alleged that all the profits were channeled to the benefit of Abuya's wife, Khadijah, who is currently residing in a palace with her forty children at Saudi Arabia.
• Apparently, the fortunes were said to be the foundation of its attempted revival, sponsoring groups such as the Ikhwan Polygamy club and the Obedient Wives Club.
• They tried to penetrate into the government's political system, and garnered sympathy from the establishment. Abuya saw himself as the caliph of the region, he had vision of paving his own way in carving his own political agenda.
• Simply said, Al arqam is in the wrong path, and intended to spread its wrong aqidah to everyone.
•  One of its tributaries runs business here in Mansoura, Egypt. It's a small restaurant delivering malay delicacies to students, offering them breakfast and lunch.
• The owner and his workers were pious men, care of their customers would be their top priority. They are also honest and often give reduced price in certain times.
• It used to be fully occupied during lunch hours, but now it's vacant, students started to boycott its product.
• Is it true, by boycotting we would have stunted its economic income, blocking it from its agenda, and glorify Islam? Even when it's economy leans more towards a capitalist approach rather than Islamic.
• Are there any confirmed rules in the Quran and Hadith stating that we should boycott products in this kind of circumstances?
• If we were to boycott this group, then why are we still supporting products such as Coca-cola and Mcdonalds, or Facebook even? companies which we were told having correlations with Israel and its allies in killing millions of Palestinians.
• It's wiser to think that it would be better to boycott the kafir's way of thinking and its system, rather than boycotting its products which would have no ending resolution.

“Katakanlah: “Siapakah yang mengharamkan perhiasan dari Allah yang telah dikeluarkan-Nya untuk hamba-hamba-Nya dan (siapa pulakah yang mengharamkan) rezki yang baik?” Katakanlah: “Semuanya itu (disediakan) bagi orang-orang yang beriman dalam kehidupan dunia, khusus (untuk mereka saja) di hari kiamat .” Demikianlah Kami menjelaskan ayat-ayat itu bagi orang-orang yang mengetahui.” (QS. Al A’raaf: 32)