Considering that most AirBnB listings are themselves breaching something like a ToS, only usually a more enforceable one (such as a tenant agreement or condo deed conditions), I don't think pointing to a website terms of service being potentially violated gives much of a high ground in itself. It also seems like a pretty unlikely combination of positions: someone who takes an "ignore the rules / pro-disruption" position on illegal rentals, but is hardcore pro-enforcement when it comes to a ToS? I'd think almost everyone who agrees with the first position also takes an EFF-style anti-enforcement position on the second one.