$50M in your bank account will more than ease the pain of "losing your life's dream". On top of that, for most people their life's dream *is* the $50M in their bank account.
It depends on how the company was funded. What usually happens in these situations is that the founders and employees only get a portion of that money; they have sold their souls (usually in the form of lots of pre-IPO shares in the company) to venture capitalists in exchange for tens of millions of dollars in investment money just to pay salaries, lease office space, etc.
Without venture capital, the company cannot get off the ground; many of these startups have NO marketable product and thus no revenue coming in for the first year at least (often 2–3+ years). They are almost never profitable even after several years in business—if they're solvent enough to last that long. This is where young, inexperienced founders get into major trouble by burning huge amounts of borrowed money on posh San Francisco office space and ridiculous perks; free, catered lunch for 50 people will cost you thousands of dollars per week. They will often have to solicit more venture capital as they run low on funds, in exchange for even more shares. This can go on for a while.
Many of the engineers are enticed to work for the company by being offered stock options—sometimes a generous amount—to make up for below-market salaries, or to entice highly skilled engineers away from more stable employment to work on the Next Big Thing at Startup, Inc. There are a lot of shares in the company floating around, even pre-IPO, and all of those need to be satisfied somehow in an acquisition. Employees might purchase shares at $X, but if the acquisition values the company at $X-5 per share, those employees have lost money on any shares they own.
When the acquisition offer comes in "too low," founders might reject it outright and/or shop the company around to others to get better offers. This seldom ends very well, frankly; see my previous post above about founders being in denial about the value of their technology!
LinkedIn shows about 60 people who work for this company (and there might have been many more who used to work there who also own shares). By the time all obligations are settled, taxes paid, etc., probably no one is going to get very wealthy off of a $50 million acquisition in that situation. Still, for a founder, an acquisition and a high-6- or low-7-figure profit in your pocket isn't too bad when you compare it to going bankrupt and selling your tech at fire sale prices!