Several reasons.
1. People late-cancel or no-show flights all the time. On many routes, Airlines intentionally oversell by a couple of seats. If no one cancels or no-shows, they end up in a bind.
2. If a flight gets canceled, passengers need to be rerouted. Many times, an airline would like to prioritize their first class or frequent flyers, so they announce an ovesell and offer cash for some peasant (/s) to take a later flight.
3. If the airline needs to move a flight crew from one hub to another, so that a later flight can depart on time, they may bump passengers.
Latest Answers