I have seen a few arguments about how porting free Linux applications to Windows is a bad thing. Why?

Let's get one thing straight. Open source software (OSS) does not mean free. There are many companies that open source their programs but charge for it in order to cover support cost. The open source portion can be compiled but it does not always come that way from the maker of the software. Also, not all apps need to be ported to Windows. This is mainly a response to the people that think Linux apps should stay Linux apps.

The main argument I have seen against porting Linux apps to Windows is "They (Windows users) don't deserve free software because they are bowing down to Microsoft and paying for a crappy OS (Windows)". That has to be the lamest argument ever. Just because someone pays for an OS doesn't put them in a "weak" user group. Windows is very easy for novice PC users. Sure, it's not as secure as Linux is out of the box but it can be protected with little effort. Novices like easy to use software (operating systems, applications, etc.) because of the low learning curve. Nobody jumps into Advanced Calculus and likes it.

Another argument is that ported apps should either cost a large sum of money (if they want it free, move to Linux) or be crippled. Both of these are horrible ideas. Crippling the software will just make the end user not want to use it. Charging a lot for it would make them seek out cheaper, Windows compatible software that performs the same task. I see why some software makers charge for their Windows ported applications, i.e. to cover extra development cost, but those charges are usually minimal. The makers of X-Chat provide their IRC software free for *nix and BSD but charge $19.95 for the Windows version. The reason is clear:

Q. Why isn't the Windows version free?
A. Building X-Chat for Windows is a difficult process, it requires quite some skill and expertise to accomplish. It takes time, and is by no means automated.

Porting apps from Linux to Windows is a great thing in the fact that it gives Windows users a chance to use software that they otherwise would never try. If you get someone comfortable using OpenOffice.org, that's one step closer for them to use Linux because it works the same on both OS's. Every piece of software that operates the same on Windows as it does on Linux breaks away a piece of the "I don't want Linux because I don't know how to use it" or the "I need X program and it doesn't work on Linux" thinking. There are so many programs out there that run the same on both systems that it is getting harder to use the second point.

Forcing Linux on someone will not get them to move to it. Just telling someone that Linux is more stable/secure won't do anything if the end user is concerned about ease of use. Applications that run on Windows and Linux is just another step in crossing over.