Eh, I understand where you're coming from, but the reality is that not everyone is going to be willing to tell a group of peers "no." We want to teach our kids that it's okay to do so, and we want to instill enough self-confidence in them to do it, but peer pressure is real and it's powerful, especially to young people.
Offering an alternative way for them to get out of an uncomfortable situation doesn't seem like a bad idea to me. We can work on building boundary-setting as a skill while also acknowledging that it takes time to build it.