The reason that so many people feel a need to keep up with the Joneses in life is that they do not want to see themselves as being essentially the "losers" in what so often is seen as a zero-sum world. That is to say, if one's neighbor has a better car, a better job, a better yard, and a better this and a better that, this often is perceived as lessening one's own self not only in the eyes of others, but more importantly in our own eyes, and in the eyes of our closest family members, for our status vis-à-vis those neighbors indicates that we are the lesser, and they are therefore the greater.
While philosophers can try to assuage people's egos by encouraging us to get a good perspective so as to appreciate many other things that should be considered as a blessing, such as good health, a safe environment, a loving family, as well as perceiving the actuality of how rich we are in comparison to other people and other cultures, with also the understanding that it isn't really the toys that we do or do not have, but the character that we are that truly defines us. All of this, though, is some small consolation, for those that measure things by the obvious and the material, and do not care about what may be happening in some other community, city, state, or principality. For what matters for these folks, is the here and now, of what one has in comparison to their neighbors and to their peers, and therefore second best or even worse, is not acceptable, and thereby one sees their neighbor that is more successful often with outright bitterness and debilitating envy.
When we are not successful in the manner that we are able to project it unequivocally to others, then we are not going to be happy; no matter how it might actually seem to be, to objective outsiders. This means, that our status matters, and it matters most particularly to those that are our true competitors in the sense that they live in the same neighborhood or the same milieu, or went to the same school, or of the same age, or basically are what most people would consider to be a fair and apt comparison to us, all fair things considered. So that, when those people outclass us, and have greater success and a higher status, then we have failed; we have not only failed ourselves but we have failed our family and have failed our truest friends, and we thereby wear our failure by the shame we feel for having failed everyone.
This is the very reason why so many people go to great lengths to "keep up appearances" because they refuse to place themselves in the unenviable position of having failed to maintain their status and therefore having lost the respect of their peers. So then, to alleviate that shame of failure or of losing face, people will push the envelope to regain the status that they need to project, of which some, will do so by any means necessary, and those nosey folks that make the mistake of "outing" those that have failed to faithfully maintain their good status, have opened the door to the unexpected and sometimes violent retribution of those that will not easily accept being publically shamed.