I strongly oppose you here. THis is the first time I am hearing!!! Tatas and Mahindras use good amount of sheet metal and hence more weight in cars. Thats proven by weight of car's.
No, You can jump on bonnet of Tata car. Very heavy to lift with one hand. Bonnet/Hatch Door/Bumpers, TATA does not compromise on these 3 body parts.
I am talking about the Zest, guys. I mean no offense, in fact I admire the Zest. But only the fact that I felt disappointed that all the metal panels are quite very flexible and thin and can be easily bent by pressing a thumb. Compared to my 2002 Indica and 2012 Ertiga, the Zest sheet metal feels weaker; and I include even the bonnet metal in this case. I hope they have made it deliberately, maybe some kind of safety?
The kerb weight of Tata cars is due to the chassis materials, additional crash-beams in doors and up-front and heftier interior parts.