They do keep records. The article that you were referring to was about how the NY police claimed that the system that they store those records in couldn't handle something like calculating the total amount of cash seized across all records.
Basically, it couldn't handle the equivalent of SELECT SUM(cash) FROM loot but it could handle SELECT * FROM loot WHERE victim = "John Smith"
Basically, it couldn't handle the equivalent of SELECT SUM(cash) FROM loot but it could handle SELECT * FROM loot WHERE victim = "John Smith"