Yes, and some of the Facebook cafeteria workers were getting up before 3 AM to make the commute in to Palo Alto, which meant that they had much more time in the mornings to think about organizing than the unfortunate techies who slept in.
The excuses really are endless in this business.
Could it be an issue of scale? The Facebook cafeteria workers were able to organize, and that was about 500 workers. Engineers are in the tens of thousands at these big tech companies and without substantial laborer support from the beginning, any potential organizer is taking a huge risk by attempting to organize.