Yeah, but look at their cash positions. I posted an analysis [1] based on their published financials in another thread; basically their revenue could go to zero and they'd be fine for a year and a half. With a more realistic 75% drop in revenues they'd be fine for about 5 years; with a 50% drop in revenues they'd still be profitable.
[1] https://news.ycombinator.com/item?id=22884042