There are different degrees of flexibility. Perhaps some people are utterly inflexible, but I wouldn't much want to know them! As for this specific case, it's not like you're going to be breaking legs for the mob. A person might believe that Facebook or Amazon are a net negative for the world, but that doesn't mean that everything they do is bad or that one's individual contribution can't be good, or at least neutral.

There are certain lines people won't cross, of course. Too much rigidity, on the other hand, is a disorder. If there's no traffic at 4 a.m. and I jaywalk, does that mean I have flexible ethics because the cost to benefit ratio is right for me... I guess. Would I murder a child for a billion dollars? No. That's over a line for me.

I guess then, yes. My ethics are flexible, depending. I have also followed the two second rule, even though I find eating food off of the floor abhorrent =(