It's simple. Don't send money via phone transfer.
OGR provides this forum free of charge to members.
I suppose they could start policing members but then that would most likely involve fees.
They aren't going to do it for free. With that in mind ebay is already set up for buyer protection, including the fees.
Buyers need to be cautious about who they purchase from. There are plenty of folks on this forum that have established a good reputation.
Having said all that. I'm sure there have been a few folks scammed by LCCA and TCA members. Especially by unsuspecting newcomers to the hobby at shows that bring home a doa Loco because the LCCA /TCA member "knew what they were taking about, and could be trusted".