My guess: there just isn't a lot of sympathy for a mechanic who, despite having experience and a family to feed, makes $58,000 per year. That is a solid 40% more than the average American, for a 40 hour work week - and that doesn't include all those fat union benefits, like 150% pay for overtime, sick leave, vacation, etc. And although being an airline mechanic is specialized work, and no one wants the average guy on the street fixing their plane, it probably isn't quite rocket science; it didn't require investing 4 or 8 or 12 or more years of education (all the while paying out of pocket for that education); and there are a lot of people out there who may be willing to do the work for less - even without resorting to "outsourcing" or "foreign workers." I bet you can find those willing workers right here in the USA - and I bet the mechanics are about to find this out.
I don't wish the mechanics ill will by any means. I do think they are being unrealistic, and although NW's demands were harsh, I think the mechanics are cutting off their noses despite their faces. It's like the old saying about sports strikes and lockouts: When you pit millionaires against billionaires, the millionaires lose - every time. Just ask the NHLPA.