Infantry vs tanks

[jivemi]

Not meaning to look a gift horse in the mouth, but in a recent try at "Totenkopf Attacks" (Scen #46) a Tiger loaded with infantry got assaulted and destroyed by a dug-in sniper. The assailant (experience and morale of 61) had no dedicated AT, just a rifle and F-1 grenade (penetration 1). After reloading tried it again; this time the Tiger got immobilized. A third attempt resulted in no assault, the sniper was pinned. A fourth try saw an assault but no more than suppression to the tank. (Except for the third try the infantry passengers dismounted, with suppression relative to tank damage.)

Question: Do snipers have special abilities against tanks, or were the first two episodes atypical events? Reason I ask is 'cuz ordinarily infantry w/o AT or good morale don't ordinarily prosper against armor. Thanks.