My definition of sportsmanlike would be following the rules, so if that "replacement team" had already played a game, it was MORE sportsmanlike to not let the replacement play. If the replacement was allowed to play, then it would just show that the "unsportsmanlike" team caved in to this kind of pressure and aided the breaking of a rule.

And, in the first place, like Andy Baker said, the opposing team should not have been asked at all. The refs know enough to follow the rules - that's what they're there for!