The reason is that even not for 1 of them I can imagine serious end user, who would use the domain to built his business at.
in addition :
gtalossantos.com may also face some TM issues, from gta.
movietrailershd.org and net - if that woud be in .com, even then it would be still reg fee value..having this keyword1keyword2keyword3 in net and org drags this small value further down.
zi1 in org and co has plenty of alternatives for ref fee : in few seconds I found for example zf1.org, zd1.org, zs1.org - so why would anyone pay some premium in addition to reg fee for name like zi1?