Since there's no mathematical advantage to selling premium vs. buying premium, I've been thinking a lot about what exactly the advantage is, and I think I came up with an answer. Being short options works most of the time, and when it doesn't work, it's easier to adjust the position if you're short OTM options. In most cases, the time decay (thea) will happen slowly, and this is what gives you time to adjust the position. Also, since it works most of the time and time decay is slow, the writer of options can take profits at any time along the way, where as the buyer of premium will only be able to take profits if there's a big move in the underlying. It makes sense to me why selling premium tends to be a more common option strategy, although I'm not sure that I've articulated it correctly.