The key question is how they are using their wealth. In the vast majority of cases they are using it with exceptional generosity - to support Auroville projects in an ongoing way, to help pay for specific things needed by the community, to provide financial help for needy fellow Aurovilians in times of crisis etc. The fact is, without these relatively well off people, and the surplus funds they have available beyond their own immediate survival needs, Auroville would not have been able to progress to where it is today. They are an essential element in the Auroville mix, and very much appreciated by the community. Auroville has not been established to create another communistic style society, with everyone at the same level.
Some people choose to live low-profile simple lives in simple houses.
Neither is 'right' or 'wrong', 'better' or 'worse' than the other. These are personal choices each Aurovilian must be free to make if the opportunity arises. We are each born into and experience circumstances in life which are most conducive to our spiritual growth, and no doubt connected with our past karma. The significance of our individual birth is only known to our innermost being, and has nothing to do with anyone else. Some people have to learn how to use wealth in a wise, generous and appropriate way.