I never took those kind of paycuts in any of the companies I've been an early stage employee in. In fact, in a couple of them I got significant increases in salary to compensate for the risk, and then options on top to further compensate for the risk.

The only times I've taken paycuts to do a startup was as a founder, in situations where I've had 20%-25% of the company or more.

If you let people talk you into taking a lower salary to work for a startup without getting a reasonably large chunk of equity, I agree with you, it doesn't make that much sense - at least not unless it's a calculated gamble for a huge exit rather than a startup where the founders are talking about a relatively low priced sale.

But most of the time, if the company has a solid idea and really need you, taking a big paycut isn't necessary. If a startup is going to be sunk by a few tens of k of difference in salary costs, then I wouldn't join it. I might get talked into deferring some of my salary (at a price) until after an A round, but that's it.

You get what you ask for, pretty much. And I always ask. If you take the first offer on the table, then you'll be paid accordingly.