In some cases, critical fixes help save companies from bad publicity, loss of potential
revenue, or loss of existing customers.

If you're writing code that is used by banks or other financial institutions, you have to keep in mind
that those companies have regulatory requirements. Violations of those regulatory requirements,
can lead to fines. Fines which could far exceed the cost of any software purchase price or continual
maintenance fees.

I know it may seem like an unreasonable request to turnaround a patch in 48 hours, but if
your customer is paying for that service through enterprise level contracts,
your company should be well compensated for the request.

Whether or not you, (the developer) are properly compensated, is something you'll have to take up
with your employer.

Happy Coding.