[unfamiliar]

There was no need for the developers to release this on the App Store. Anyone installing a Haskell IDE is perfectly capable of installing an app normally.

[seanmcdirmid]

They are charging money for it, so that is reason enough to use the Mac app store. If it was free, then I totally agree.

[delinka]

They can charge for it on their own web site. No requirement to go through MAS to sell Mac software. If people are having a problem with this, complain to the author of the software.

[seanmcdirmid]

Charging money is hard if you aren't a big company, which is why app stores have been super successful.