This may work in Singapore, but I would say it has limited appeal as-is, elsewhere in SEA.
There is some friction to finding and stopping for a snack in the west, whereas there are little street-side stalls selling drinks and snacks every 50 yards in most SEA cities, and the transport is often tuk-tuks and rickshaws rather than taxis.
Additionally, I doubt people will be willing to pay for premium western brands (which they're possibly unfamiliar with), with a further captive-audience premium, unless there's a "conspicuous consumption" aspect to it - rather difficult in a vehicle, as opposed to a glass-fronted coffee house for example.
Good luck nonetheless - they may have some success with the right products, though I can't think immediately what those would be.
> there are little street-side stalls selling drinks and snacks every 50 yards in most SEA cities
This makes the absolutely spread coverage of 7-11 sound more romantic than it is. There’s a place I can stand on my street where I can see 3 7-11s, one Lawson, and one FamilyMart.
I predict it will be a hit in the Philippines, too. Every hundred yards or so there's a 'sari-sari' Mom & Pop convenience store but here's the thing: people are accustomed to being able to pick up snacks or drinks for some pocket change. And all the Grab drivers need to do is look at what those stores usually don't have in stock and offer that instead.
Yes, with the right products it could possibly work, but not for simple snacks, which as you say are widely and easily available for very cheap.
Especially if they are charging hotel mini-bar type premiums.
I use Grab all the time but only motorbikes and can't imagine these drivers carrying snacks around. I don't have stats but I'm pretty sure that at least here (Vietnam), the overwhelming majority of Grab users go for bikes.
There is some friction to finding and stopping for a snack in the west, whereas there are little street-side stalls selling drinks and snacks every 50 yards in most SEA cities, and the transport is often tuk-tuks and rickshaws rather than taxis.
Additionally, I doubt people will be willing to pay for premium western brands (which they're possibly unfamiliar with), with a further captive-audience premium, unless there's a "conspicuous consumption" aspect to it - rather difficult in a vehicle, as opposed to a glass-fronted coffee house for example.
Good luck nonetheless - they may have some success with the right products, though I can't think immediately what those would be.