The ancestors were practical people.
When linguists discovered that, by comparing words from daughter languages, they could reconstruct a vocabulary for a language from some 6000 years ago, predating the invention of writing, they were ecstatic.
In our understanding of the past, archaeological artifacts will take us only so far. To really understand how a culture thinks, we need to know what it says.
To the scholarly world's everlasting disappointment, what we can reconstruct of the Proto-Indo-European language really tells us very little about the ancestors' society, culture, or religion.
What we do know is that they had two words for, shall we say, “breaking wind.”