- Stainless steel utensils lasts for decades. My mother keeps utensils that her mother gave. Indians love products that last that long. On the other hand, even Tupperware utensils don't last more than a few years.
- Microwave ovens are still not widely used in India and Indian style of cooking cannot fully leverage microwave. Thus, gas cooking is the most used way to cook. Stainless steel vessels are good conductors.
- More importantly, stainless steel vessels are 100% recyclable and thus there is a good scrap value. Thus, if you don't like a certain model take it to a shop and get a new one in a buy-back offer. Indians love that. They constantly recycle their gold ornaments and utensils for ever more newer models.
- Compared to Tupperware containers, stainless steel is relatively cheap.
- Stainless steel vessels are more aesthetically pleasing to an Indian eye.
So you have got low cost, long life, resale value ==> Enough to keep Indians happy.