The big problem from my point of view is management. Everyone pushes responsibility and work all the way down to the developera so that they do basically everything themselves from negotiating with the customer, writing the requirements (or not) to designing the architecture, writing the code and testing the system.

If they're late,they just stay and work longer and on the weekends and sleep at the desk.

This is the only part that sounds bad? Negotiating with customers may require some help as well but it's better than having many layers in between.