[munksbeer]

This is true in complex scenarios but not true in other finances scenarios. For example, there is a reason why any electronic exchange will use integers with implied decimal precision as the wire format and will continue to use such representations before and after encoding/decoding. We do not need to do hugely complex operations, it is mostly simple comparisons and some simple maths operations. We absolutely need exact precision and speed and it is difficult to get that when using doubles.

In parts of the stack where things are more complex and outside of the critical path, then yes, you use floating point.

Also, it isn't just that rounding the cents isn't worth it, it is that if you work with implied decimal integers with an implied 2DP, then you're going to end up with massively inaccurate results after a few operations.