Well, believe it or not, but that's the wage that built Gandhinagar. (Note that due to inflation, that would be the equivalent of about rs.250/month today). Perhaps on paper the workers were making quite a bit more, but this was then "deducted" for their nominal food, housing, etc. In any case rs.150/month was their actual take-home pay. I couldn't believe it either, and triple-checked to be sure.
India has come a long ways since then. Although the working conditions on construction sites are still far from good enough, I don't see children on them anymore, and those same workers would probably be taking home rs.5000/month today -- maybe rs.3000/month in places where contractors are more brazen about skirting the law. In any case: much better.
Clearly, this picture is vastly different from the original picture you painted. I feel let down by the fact that you did not mention how outdated your original description was.
I live in a newer area of Bangalore and my apartment is surrounded by construction sites. There's a settlement of construction workers right across the road. What we see is small temporary one-room houses with satellite TV, and families that dress up and go out every Sunday. We even see them buying basic cosmetics in the local stores. Kids are not visible in the day time either in the settlement or on the construction sites, and I like to hope that they are actually in school.
India has come a long ways since then. Although the working conditions on construction sites are still far from good enough, I don't see children on them anymore, and those same workers would probably be taking home rs.5000/month today -- maybe rs.3000/month in places where contractors are more brazen about skirting the law. In any case: much better.