I think it will attract a lot of people who are wanting to deal in illegal drugs (and other, more dangerous illegal items) and become a marketplace for such. The difference here verses other illegal drug sites is that the bar for selling is much lower so it would be easy for law enforcement to conduct sting operations from people buying drugs on these sites
There is no signs of this yet. OpenBazaar developers made it clear it is meant for legitimate businesses and will be attractive because it has no fees. However they also said they can't control what will be done with it as it is also censorship free but they hope the code will be forked for illegitimate usages.
They do acknowledge that the market could be used to sell/buy illegal/disgusting things like childporn, sex trafficking, illegal drugs, and a # of other abominations since there can be no censorship?
If they acknowledge that and do nothing to at least outlaw those activities...Then I truly, sincerely hope OpenBazaar gets banned/becomes illegal to use.
Sure so the government should also ban bitcoin because it can be used by criminals right? What about the USD? We should also ban cars so criminals can't runaway.

That's a stupid argument. Bitcoin can be used as a medium of exchange, just like cash, it's not an actual marketplace with listings and buyers and sellers. It's just a currency and its users can be tracked via a public ledger. However, from what I've heard of OpenBazaar, it is a marketplace that can not restrict or censore any items being sold, which makes it a breeding ground for illegal activity that can't be stopped by traditional means.
Only manpower(Agents pretending to be buyers/sellers), would be able to track down criminal(s)/criminal activity on OpenBazaar, and I'm sure if it gets big, federal police won't have such manpower.
The same argument you make with bitcoin is applicable to openbazaar. Just like bitcoin is a free decentralized platform for money, openbazaar is a free decentralized platform for commerce. This is just the logical step further and no one should have the rights to censor global platforms. Should we also censor internet which is a free decentralized platform for communication? Should we censor YOU because of potential criminals?