I've heard He could turn weed into marijuana, too.

Of course it would, but in a way that's the problem. It's easier to explain the absence now (though I do think it happens, however rarely) than the presence then. I'm tempted to say it's the same reason Jesus forbade the Disciples to reveal His divinity (and apparently revealed it even to them fairly late): Proof denies faith. Free will's vitally important because of Pithy Pet Phrase #1: Love can't be coerced. If God comes down from heaven and slaps you around with His divinity it's no longer a question of faith He exists, but tolerance of that self evident fact. Incontrovertibly demonstrating His existence removes the option of doubting it, an option that must exist to have any choice at all.

Faith can be and is confirmed, but that's "retroactive proof", a Catch 22. I believe it happens because it happened to me, for which I'm very grateful; nothing is more terrifying than BELIEF in Christ while minuscule doubts make FAITH impossible. I can't say what gets one over that hurdle; I think it's as unique as the individual and his relationship with God, but I also think it vital, so I can only recommend scripture, prayer, fellowship, and a lot of "Lord, I believe; help my unbelief". Curiously, the bible says pretty much the same thing; fear and trembling and all that. All of that incidentally makes legit miracles as rare as unshakable faith, on its way out 2000 years ago and waning in popularity since. Miracles take faith to move mountains, not mere belief, and once again, won't create that faith, only confirm it. "You shall not tempt the LORD your God as you tempted Him in Massah" is one of the older prohibitions (and becomes more applicable in context).

Basically, miracles are less common because they're almost never used to prove faith, and really not even useFUL; if rising from the dead won't convince someone, nothing else will either.

Thanks, but I have to admit I borrowed a fair amount of it as well.