[RandallBrown]

There's a book I read as a kid that takes place in the sort of near future after we've run out of oil.

The only people that have plastic in this future society are extremely wealthy and poor people "mine" old landfills looking for plastic to sell.

https://en.wikipedia.org/wiki/The_Ear,_the_Eye_and_the_Arm

[pfdietz]

That's not plausible, IMO. Plastic may become somewhat more expensive, but it doesn't require fossil fuels. Overall secular increase in societal wealth should overcome any transient increase in price.