It's a result of too much information being not useful. The contract cost is activation only, there's no per-second consumption. It's just people didn't know if they were actually producing enough to have trades constantly on, so they asked me to add phantom consumption on the resource screen. It doesn't actually consume it, it only shows the average consumption per second.
You can actually see that if you switch off all your produciton for valuables, the number you have in stock will not decrease.
Also FYI, all red number on the production screen are not necessarily ACTUAL consumption, it is consumption IF everything is consuming as it should. For example, your troops want to consume 1K/s food and 1K/s iron. You produce 1K/s food and 0.1K/s iron. The red number will still show -1K/s for both food and iron, even if in reality you consume only 0.1K/s of each (since that's the bottleneck). Previously it was showing actual consumption, but then it was confusing, how come I go increase my iron production and suddenly my food consuption spikes 10 times.