There are indeed malicious individuals here like anywhere else but the real problem is the lack of involvement from the governance team, as I see it, because what this really does in effect is encourage the abuse to continue when there is little to no risk of banishment, which I feel is truly the only thing that might deter a merchant from attacking a competitor such as yourself.
For the non-merchant, second life is an open door where they have absolutely nothing to lose because they can just as easily copybot their way back in with new accounts, say what they want, pay nothing if they wish when it no longer seems to be the issue because linden lab truly, has lost control in this respect.
Second life from an economic perspective is doing terribly so merchants who are barely getting by will naturally feel threatened by new merchants who are far more cabable and making profit when they aren't. You see this all over so, the fact that you have some haters means you are a capable merchant interpreted as a personal threat because no one who has something to offer this community, that people might actually want to purchase, will deny you your ability to sell unless it was obvious enough how much better you are then they are and that of course, won't sit well with them.
What you can do as I've alluded to, is just do nothing because it is doubtful you will beable to keep up with their mischief if they really have it in for you. Sales may or may not be effected on the short term but second life shoppers are not as dumb as you might think especially at your prices or if a product is desirable as I have found so, wait it out and if you're still having problems, contact me in world in a couple of months because I have an idea and I would love to help you out here if I could.