I recently interviewed at a startup that also happened to have a job posting on AngelList at the time, and the salary/equity offer they gave me was actually below the range proposed on the AngelList posting (I hadn't applied through that posting). When I brought this up their HR contact attempted to explain that the posting was meant to be for a Senior Engineer, which I'm not...presumably hoping I hadn't noticed that they had a separate posting up with an even higher salary range titled "Senior Engineer". I declined their offer, but the negotiation was a very valuable learning experience (as in, I did everything wrong starting by being the first one to give a number, and learned not to do that!)
I was talking with a start-up with two founders, and they wanted me as their first employee to work for free for 3 months, in exchange for 1% of equity.
I told them that offer had poisoned any further conversation.
I read a lot of salary-related articles and discussions(due to my startup) and I've seen many examples like yours. This is nothing other than a click-bait scam. It is very unfortunate. You think upfront-listed salaries are a way of eliminate unmet expectations during the interview process. And all you get is companies listing high salaries to attract the top talent and then not honoring the promise.
Don't be so negative. They'll pay you $1xx,000/year...once they raise funding in 3 months.
In all seriousness, I'm not sure why so many people assume that the salaries posted on AngelList should be taken at face value. With minimal due diligence, it's clear that a lot of the startups are unlikely to have enough funding or traction (in the form of revenue) to support the salaries that they purport to be offering. As you pointed out, they're just trying to get warm bodies through the door and hoping a few of them will drink the kool-aid.
Getting someone in the door by lying to them doesn't seem like good round on which to start a relationship. Unless you're desperate, it's stupid to accept an offer where one party started the negotiation by misleading you.
I recently went through a very similar ordeal. After kicking ass for two out of three months of contract-to-hire gig, the company said they loved my work and wanted to end the contract early. Awesome. Then they dropped a full time offer for 20% less than the minimum they advertised on Angelist, well below the market. When I tried to negotiate towards something more reasonable, they pulled that same line about the range being for a very senior dev and were resistant to negotiation, even though the advertised range is big enough to fly a jetliner through and they clearly know that no self-respecting senior dev would work for the bottom half of the advertised range. They just closed a huge round and could have paid more, but chose not to.
I ultimately declined their final offer which they seemed pretty surprised by. It's hard not to take personally after working there and proving my value for two months. Instead of a bum offer from a company I just met, which is no big deal, it really felt like people I thought were my friends were trying to take advantage of the situation. I probably will never do another contract-to-hire. I'm not interested in companies with a try-before-they-buy feeling about candidates, because I think it belies an unwillingness to value and respect the work of talented hard-working technical people.
I made some money and got valuable life experience from it, but I'm still sad about how it went down. There's enough credible salary information out there that companies are really doing everyone a disservice by pulling an extreme lowball on a candidate they want.