Being in "eternal alpha" isn't really a problem. Devs nowadays will release their indie game at a AAA game price once their game is only 10% done. But haven is free either ways.
I can't really think of any advertisement made for this game. Honestly would never heard of it before if it wasn't for friends. More people should know how great HnH is.
Is it because the servers wouldn't be able to handle, let's say twice or thrice the player traffic?
I'd just like to hear why adding it on steam would be a bad idea.