I thought that too, but then it would get modified when you eat food and drugs, I think 15 would be enough to give some options, but not too many.
It seems like the harshness of these nerfs to sneak was a way to deter people from doing silly things, but has left sneakers with very little options in it's severity.
For example the amount drained when turning a SB on and off and the speed of SEC drain increments are so harsh in combination together, having only one or the other as an energy drain variable would have worked fine, with both in play the consumption rate is astronomical, at least 1 should be scaled back a bit, and I think that is the weight penalty. Tripling your SEC consumption for holding 6 more kilos than 9 seems very excessive.