Yes, space efficiency is surely to be considered, but bit perplexed about the thought of substituting, in the sense of pure equivalency. In my experience, this works only to some extent. I mixed up sauces out of paste plus water but taste and texture are different.

Heard about the Heinz story. Sounds like a myth to me but somehow I want to believe it!

In fact, their ground coriander is uncontaminated (albeit pricy, unless you buy their catering-size jars).  The confusion arises from the fact that in British English (don't know about American) "chilli powder" often refers to the blend of spices used to make a chilli con carne, which is why I always refer to the pure spice in its powder form as "ground chillies".  Anyhow, your own fault for using Schwartz instead of TRS/East End/Rajah/Shan/Laziza/Mehran/whatever, or even Mrs Balbir Singh's !