I'm going to go with that horrendous, non-absorbent, 1/8th ply toilet paper that gets stocked in public and office bathrooms.
I'm on Team Bidet now, so it doesn't bother me as much as it once did... but the stuff should not exist.
I'm guessing that one day, the people who buy the stuff will figure out that it they're not winning if it costs one-third the price of normal TP when everyone has to use ten times more of it, but who knows when that day will happen. Because it hasn't happened yet.