At the end of Croft Manor you uncover your mother's tomb, hidden in the bowels of Croft Manor. The rest of the manor is in complete disrepair--trees broken through windows, rain coming down in the foyer, and other signs it hasn't been inhabited for a while--yet this room has 10+ lit torches going when you walk in. This isn't unique to Tomb Raider though. Most games with ruins, caves, tombs, etc. have inconsistent evidence of habitation. However, some designer at Crystal Dynamics obviously thought of this inconsistency, so each of the torches has a gas pipe running up to the sconce.

My first thought was: "Wow, what an amazing detail." My second thought was: "That still makes no sense." Why would this room that has no entrance and is intentionally hidden need to have gas torches going 24/7? Wouldn't the huge gas bill each month raise questions, thereby risking that the room is uncovered? If I were Lara's uncle and wanted to her deemed unfit to manage the Croft estate, I would definitely point to the huge amount of money she spends on gas each month as evidence of her profligacy.

In conclusion, great job on the extra little details but in the bigger picture they still make no sense. Any other examples of stuff like this?

That is really weird. Maybe the gas only turns on when someone trips some hidden mechanism? At least they tried, I guess.