A few years ago, the only "halal" signs one saw were on butchers' shops. But now halal is turning into a global brand – as highlighted in a BBC documentary proclaiming that "The Future is Halal".

The Arabic word "halal" means simply, that which is permitted in Islam (the opposite being "haram", or what is forbidden), and until recently that definition meant little more than consuming meat slaughtered in a religiously compliant way, and avoiding pork and alcohol. Now there is an almost endless list of halal products. The hashtag #IslamicProducts on Twitter recently satirised the increasing absurdity of some of these innovations.

The most lucrative of these by far is Islamic finance, which seeks to eliminate usury from all transactions and which has been transformed from a niche product to one available on the high street in the UK.

There is halal perfume, toothpaste, "beer" (it's awful), bacon (delicious), cosmetics as well as "halal" hotels and holiday resorts. The definition of halal has become so broad, it seems to encompass everything that caters to Muslim sensibilities. There is even a World Halal Week that showcases such products.

A growing Muslim diaspora in the west, and a rising middle class in Muslim countries constitute what is estimated to be a $2trillion market in halal goods and "experiences".

This demand seems to be less a hardline religious fixation, and more a theme, a lifestyle, that Muslim consumers would prefer – one which embodies the spirit, as well as the technicalities of halal. When holidaying with my mother and three sisters, all who wear the hijab, I would be grateful (and certainly pay more) if a hotel or resort had female-only pools or spa facilities. The fact that businesses are beginning to provide for this is, at best, the epitome of non-discriminatory capitalism, catering to customer demand.

The provision of halal products in this way is almost a secular phenomenon in its indifference to anything apart from consumers' lucre. At its worst, it is exploitative, coming up with products that make a tenuous link with the concept of halal – patronising customers in the way that some suppliers seek to create "girly" versions of mainstream products.

The line between satire and reality wears thin sometimes. In a mocking attempt to come up with new halal products on Twitter someone suggested an Islamic car, with a button that plays a prayer – only to realise that it already exists.

But there is something comforting in the levelling, integrative power of profit. In Islamic finance conferences bearded sheikhs and white Harvard MBAs sit and work side by side. The University of Oxford hosted the first Islamic branding and marketing forum in 2010 where one of its keynote speakers said that "growing commercial opportunities can bind Muslims and non-Muslims in a common humanity even though until now religion has long been considered taboo in mass marketing."

This is increasingly evident in Ramadan marketing on Arab television for example, where the focus is now on selling, underpinned by a religious theme, but not on the holy month itself. According to a British advertising agency, the religious theme shouldn't be pushed too far, as it recommends that one "avoid stereotypical imagery of prayer caps, rosaries, mosques, looking at crescents and so on". Sort of like what happened to Christmas.

And as quickly as western financial institutions caught on to the potential profitability of Islamic finance, western advertisers have taken the lead in Islamic branding, with one leading company declaring in its mission statement that "in recent years global marketers have started to enthuse over the size of this prize and ruminate on the importance of cracking it – but we believe the challenge is in managing it knowledgeably, sensitively, and profitably for the long term".

In a way this is not dissimilar to how industries cater to other consumers with ethical or lifestyle criteria, to vegans or the pink dollar. A friend of mine has spent much money, effort and time avoiding any unethically produced sportswear or running shoes.

But the halal market has its foundations in the spiritual. It is unsettling to hear professionals talk about the "earnest Islamic consciousness" and how best to make money out of it, using a concept that is in essence meant to guide Muslims to a good and wholesome life. And it is easy to cross the line between catering for a community and inadvertently ghettoising it.

While I am grateful for London suppliers of halal bacon and sausage, I won't be spooked into buying halal Tupperware or teabags soon. Yorkshire Tea will do just fine.