A disproportionate number of VIPs ran a business on the forum -- they likely donated the 50 BTC as a way of giving back to the community -- and many businesses failed for one reason or another, and failed businesses often have similar characteristics of a scam. 

The barriers to entry into most "industries" were very low back then, a lot of community members were more trusting with their coins than they probably should have been, and it took longer than normal for things like poor management and poor security practices to be exposed.

I suspect that some of the VIPs who have only one or two posts likely were involved in some kind of shady dealings and have subsequently deleted their posts to cover their tracks....this may have been the result of outright scams, or it may have been the result of poor management and/or deals that went poorly.