Unless it was the classic 5 v 1 situation where a single 88mm gunned Tiger with full IR range was facing off 5 range-shortened Shermans, I don't see there being any encouragement for Sherman drivers to be cannon fodder.

In any case, most tankers tend to buy the "hero" heavy and medium tanks where in reality the WW2 battlefield had a lot more light tanks and SP guns with the heavies being rare. It is a noble effort to seek greater realism, but when a Panzer IV costs as much as a Tiger I, it wouldn't be hard to understand why most go for the heavy tanks, and historical accuracy isn't quite there anymore due to the bias to heavy classes.