I've never bought Leprechaun without intending to gain wishes, I believe.
Leprechaun misfires far more often than it hits and I have witnessed better players than me open with Leprechaun and win.
Well, since buying Leprechaun is evidence for a good deck, the "only one player bought it" statistics don't work here. The statistics for people who open with it look quite bad (silver/leprechaun openings have a 47% winrate) but the sample sizes are smaller.
I don't think I've ever opened Leprechaun, though I have seen my opponents do it a bunch.
I don’t see the relevance of these statistics. My point is that Leprechaun is first and above all a Gold gainer. The Hex is a downside, the Wish is an upside. The latter matters more but you get the Hex more often than the Wish.
So Leprechaun basically tells us that a vanilla Gold gainer is too good for $3. Bandit says, it is too weak at $5. So we get $4 as the correct price.
The question is whether it is a weak or good $4 and how much the two extras of Apiary interact with that. I think that it the vanilla gainer would be a slightly weakish $4, but that the two extras of Apiary more than make up for that.