In recent times, I’ve bought Hadean Lands and Dominique Pimplemouse (spelling).
Because of the existence of itch.io, I decided I would sell my re-take of my Apple II game Leadlight, Leadlight Gamma, which I released earlier this year.
wade-clarke.itch.io/leadlight-gamma
leadlightgamma.heiresssoftware.com/
In the context of not having sold an IF game before, I realise that knowing that I was going to sell it to strangers was motivation to push it further technically and polish it even more than I might have otherwise. I am a big fan of the final product, though I did not expect to sell a ton of copies, and I haven’t.
In some topic somewhere on this forum, at some point in time, someone said something like ‘The traditional parser community don’t buy many IF games, as they’re used to them all being free.’ I don’t have a LOT of data to go on, but looking at who has rated or reviewed LLG, that seems to have been bourne out. They’re not anyone I know. On one hand, that’s cool - you can just put out your parser game and, if it looks cool, strangers might try it. On the other hand, I thought some of the people who gave the game a 10 in IFComp might buy Leadlight Gamma 
As far as retakes go, it’s pretty novel. The game mechanics have parity with the Apple II but there are tons of extra conveniences, IF tech things, extras. Built-in music player, comes with all the graphics (though they come out small on iPads - grr!), etc.
So I can say that I have not planned to make a fortune from IF, but my own inclination is now to sell the IF games I make if they’re standalones. They’re still very cheap, and it’s easy for me to sell them, and in my sample size of one, the commercialising did help me push the quality of the project. Whether it wise to sell them if the staple audience of parser IF aren’t the people who would pay for them, I don’t know!
One important point is that there are now means to be able to sell your IF game without enduring ongoing resource drain. For instance, to be in the iTunes/App store, you do have to pay annually to be an Apple developer. But to put your game on itch.io, you don’t have to pay anything, and then you also decide how much to pay itch (as a percentage) if you sell a copy. I decided to pay them a fairly standard percentage for their great service, but when I’m not selling any copies, I pay nothing. That is a big attraction. Au contraire, to keep my pre-label indie music on iTunes is mostly costing me money now that that album shifts units at a trickle.
I also talked a bit about the going-commercial aspects of LLG on this podcast:
gamebits.net/2015/07/15/indi … ght-gamma/
-Wade