A 27% tariff on toilet paper won't effect the supply; what will effect the supply is people creating self fulfilling rumors that you better stock up because there's going to be a shortage.
"How bad will this winter be?" An indian asked his chief.
" I don't know but it is good to be prepared. Get some firewood ready" replied the chief.
The chief then called his friend in the national weather service to ask him. " How bad will this winter be?"
The meteorologist said "this will be a pretty cold winter"
The chief then told his people what the meteorologist said. A few weeks later the chief called to ask again, just to be sure.
"Well," said the meteorologist, "its gonna be worse than we thought this year."
Again the chief relayed this to his people and told them to put out more firewood.
Right before the winter came, the chief called the meteorologist once more to ask, "how bad will this winter be?"
The meteorologist said "it's gonna be worse than we thought"
The chief thanked the meteorologist and asked him "how do you get such accurate information?"
"Well, we have teams of scientists that study patterns to predict what the weather will be like. But we found that the most reliable method is to just look at how much firewood the native Americans put out"