As others have rightly pointed out, much of what is written on here at the moment has to be seen in a certain light: It's not simply a matter of hating LVG and wanting him sacked at any cost. Sure, we have our share of entitled/impatient/foolish/childish fans who would no doubt be kicking and screaming regardless of the circumstances, but this is neither here nor there. All big clubs have fans like that.
What this is mainly about, however, is that a huge amount of United fans lack confidence in the club's decision makers. LVG isn't the main concern for many of those fans. They're much more worried about what the people behind him are up to. Standing by the manager isn't the worst approach you can take, as a fan, but it becomes complicated if you have serious doubts about his employers. Standing by the owners is a very different concept, and something which probably comes far less naturally to most fans.