Yes, I totally understand the desire to try the app first. For the launch version, we had no choice, but to go with the Mac App Store.
I have started to investigate alternative distribution channels (which then would allow trials, too), but that will take a while to implement (so, I can't promise anything concrete at the moment).
You can request entitlements, such as network access, but you need to justify them in the App Store review process. Given that Haskell for Mac is pushing the boundaries of what is available on the Mac App Store, I wanted to err on the side of being too conservative for the launch version.
I will certainly work towards network support in coming releases.
There is nothing wrong with Haskell. It's just that writing an IDE is a lot of work and nobody bothered to invest that work so far. Haskell for Mac changes that. (I'm biased — I wrote it.)