why would that be relevant? the only thing I can think of is to prevent judges from stealing spectral tigers during deckchecks.
I'm not sure a judge stealing a spectral tiger is any more relevant than a player stealing it... It's still stolen either way, and somebody is going to get a banned from playing/judging.
My guess, like yours, is that it's to prevent any sort of situation where theft could occur at all.
4th Place, Day 1 US Continentals 2008 (22nd place overall)
1st Place, Ashenvale Realm Champs 2008
1st Place, Seattle Regionals (7/5/08)
1st Place, Seattle Regionals (5/31/08)
1st Place, Spectral Safari (3/1/08)
1st Place, Seattle Regionals (1/12/08)