If it actually were exceedingly rare for the price of toilet paper the make a significant difference in people’s financial situation, then I suspect toilet paper manufacturers/retailers would realize that this means they’re leaving profit in the table, and they would raise prices.
That is not how markets work. As long as there is competition, prices drop to the bottom. It would take concerted effort to rise prices, e.g. by forming a cartel. That's illegal for that reason.
You can also calculate the situation for yourself. How much does a unit of toilet paper cost and how long does it last?
To me, the situation looks more like GP could be right and doubling the price of toilet paper doesn't kill people but rather stabilizes the situation. Besides, it's always possible to substitute the usage.
