You are missing the core point - the income for an average person in India is significantly lower than the US or UK. Therefore, you can not directly compare prices of products across countries regardless of the costs of the product itself.
Some metrics to look at
GNI(PPP) Per Capita in Int$ : India - 6,980 / UK - 42,560 / USA - 60,200 [0]
GDP (nominal) per capita in US$ (World Bank) : India - 1,940 / UK - 39.720 / USA - 59,532 [1]
One of those countries, is not like the other two.
[0] https://en.wikipedia.org/wiki/List_of_countries_by_GNI_(PPP)...
[1] https://en.wikipedia.org/wiki/List_of_countries_by_GDP_(nomi...