The Pesach offering is unique: if brought in communal tumah, it may also be eaten in tumah. The reason: the Pesach's essence is its eating — the altar service is instrumental to the meal. Since the eating defines the Korban, the tumah that permitted the bringing also permits the eating. The five items above are different: their essence is the service itself (the Omer's waving, the Shtei HaLechem's tenufah) — eating is secondary, and so tumah permission does not extend from bringing to eating.