Two sets of standards is never a good thing. Any show of preferential treatment in a situation that an even playing field is expected, is not only unfair, but unethical. It creates an atmosphere of resentment and hurt feelings. If it's allowed to continue, no one will participate.
Standards generally should be the same. But for some cases they should be adjusted for the participants. Based on age or sex or special needs.
ie a very young player, or a special needs player. Or academically you do not expect the special education students to perform the same as the regular students. In PE class, we always had one requirement for the guys and a different one for the ladies because there is a difference in men's vs women's body strength.