It is just a question about value of money.
You might think that people who bragg value money a lot, but it's the opposite. They bragg about it, because for them, money's value is very low, and people get offended because money value is very high for poor people.
That said, I wouldn't want to live in a society where you can't tell others what you have purchased or accomplished so as not to make them jealous. I understand the point about people's father's cars, and totally agree, but this is not the kind of envy that is productive. I dont' give a **** when people speak about how well their families have succeeded, because it is not their own personnal success. Truly, I don't get pissed, I just don't give a ****.
On the other hand, if a friend of mine tells me about his success, I'll get jealous. But it is a positive jealousy that will drive me to do as good or better. I will have no condition like "if I can". I'll just do so that I can.
If we suppress merit in the society, it might comfort some people, but it will pull the society's progress downward. If you decide to quit working and live on subsidies, you have no right to bash someone who decided to continue. Well you have the right to bash him, but it would be unfair if you did so that the state can remove the incentive for people to work their ass off and gain money. Family has got (almost) nothing to do with that. I know people who came from very poor families who decided to work their asses off and that now have a lifestyle which is way more that comfortable (e.g. big house, two cars, one of them being a Porsche Turbo S). On the other hand, I know people from super rich families that failed their lives totally, because they were used to having everything given to them, and now that they are on the workplace, they are ****ed up.
On another hand, I know people from rich families that had great successes for their moral was boosted by the family's past, and people from poor families that lost every incentive because they considered it unfair that some were rich, some were not.
This is all a matter of personnality. The best solution to this problem, so that you feel comfortable with your life, is to take responsibility for your own actions. The beauty of life is that you can acheive everything if you really want to and if you do everything in order to. If people start losing the idea that their outputs can be acheived with external intervention, no matter how rich their family is, they'll spend a miserable life.