[abhi3]

India has 22 official languages & English is the lingua-fraca.(https://en.wikipedia.org/wiki/Languages_with_official_status...)

Almost everyone middle-class and up can atleast read English so makes sense that online retailers use that.

[blreng]

In the southern parts of the country (Karnataka, Kerala, and Tamil Nadu), I have seen even the poorer class, auto-drivers, and cab-drivers too speak English fluently. :-)