Why bother with source code?
Users of Linux often prefer to download source code and compile it themselves instead of downloading executable binaries. Some Windows users do this also, but the inclination to do this seems to be much more common with Linux users. Many Linux users want to download source code and compile it themselves because they worry about malicious code in binaries and feel that by compiling it themselves they avoid any malicious code that hackers might be trying to get them to run. This probably gives a false sense of security because few people actually take the time to look at the source code and check for malicious code.
Maybe they don't want to take the time and effort to look at the code. Doing a careful security review of source code is actually fairly difficult and time consuming, so few people are inclined to do it. The result is that most source code that gets downloaded gets compiled and run without much review at all. If that's what you're going to do, why bother with the source code at all? If you're not going to look at it, just save yourself the work of compiling the source and download binaries.