Financial institutions and individuals with large amounts of money are the ones least likely to be affected by unanticipated inflation. While their resources may have less buying power, the dynamic nature of money makes it easier for someone with excess to make up for sudden weakness in a currency.
Individuals closer to the poverty line are most affected by unexpected shifts in prices. People who have fixed incomes or are on a salaried wage see the biggest impact because the inability to directly control the amount of money earned can greatly hamper personal response to inflation. The biggest concerns about inflation come down to worrying about a lower standard of living, and funds set aside for retirement may be stretched even thinner by sudden changes.