Apparently if you hold a garage sale in the San Antonio, Texas area you can be fined. And if you choose to thumb your nose at the "silly ticket" you can be included in one of their "Warrant Roundups."
Basically, if you hold a garage sale, get ticketed for some illegal act associated with it, and do not pay for the violation, you can be arrested. Now it is obvious that should expect to face an arrest if you don't take care of a citation within the time-period required.
What is interesting though, is that you can receive a citation for holding a garage sale in the San Antonio area. Now I do know that there are some municipalities that limit when and where you are able to hold a garage/rummage/yard sale, but I have never witnessed a "violent garage sale." I can only assume that these are reminiscent of certain holiday shopping days where over-zealous shoppers trample each other to get the last, whatever, before the store closes, or before another shopper can grab it.
I tried Googling "violent garage sale" and didn't come up with much, other that a reference to someone being stabbed with a pitchfork. Really though, if you are taking a militant approach to these types of sales, you should seriously rethink your hobby and/or priorities. Most of that stuff is just not worth it.