The one thing you can find in every single town in the UK (I don’t about other countries) is at least one - and usually many - Indian and Chinese restaurant/takeaways. Therefore they must be immensely popular.
So, why has no-one started a national chain of Indian or Chinese fast food restaurants. The concept works for other cuisines (McDonalds, Pizza Express etc). The food is ideally suited to being packaged for takeaways, and for fast food serving. I would have thought that with the benefit of national branding it would be a sure fire success.