Some of it depends on what the wealthy JWs did with their money. I have noticed that JWs who are wealthy tend to be in the construction business ... one of the few really accepted professions for JWs that allow for wealth generation - unlike the well accepted janitorial trade.
Often the wivesof wealthy Jws in the construction trade had more time to Reg. Pioneer, because they did not have to bring in extra income ... and if the husband's business was large enough, he did not always have to be at the job site, and could Aux. Pioneer ... this, combined with free labor and materials to help with Kingdom Hall construction, made such couples seem very dedicated and involved JWs - and this helped them to fit into the inner circles ... and this is how their children sometimes escaped more serious treatment.
Although, that is not always the case, and some of it is perception. We tend to assume some people are wealthy, when they may be struggling. We may assume they get away with sins other don't, but we may not always know all the details.
At one time, my family and I were viewed as "wealthy" because we paid cash for a very nice large home in the country - with a great view. I was a professional engineer ... and comparatively better eeducated than the average JW in our congregation. This created the ambiance of upper class, and with that assumptions about me and my family that were wholly untrue.
For example: The only reason we were able to pay cash for our home was that we moved from a vastly more expenseive area where homes cost 4 times what they did in our new area. Otherwise, we struggled because we lived on one income. My kids did not get away with more than other JW kids, and were often treated more harshly and with greater scrutiny because of the perception that we were well off ... got to get those rich kids! and keep them in line ... and we often felt that others were given more slack because they were not as well off.
Once it was merely rumor that I was not in complete harmony with Watchtower doctrine ... I found out real fast that 99% of those JWs I thought were 'friends' were not at all friends, and quite willing to dump me at the first sign of trouble. Their friendship was shallow, regardless of whether we or they were wealthy or not ... it all mattered not ... because once loyalty to the organization is merely in question, then the assumption is guilty until proven innocent.
Yes, I agree that many times wealthier JW families got by with more ... but there are reverse examples ... and I believe that what has more to do with it, is personality, good looks, knowing how to play the game, know who to butter up, ... and often times wealth seem to follow good looks, personality, and good politics.