Not everyone is allowed to live in military housing on Fort Bliss in El Paso, Texas and the same goes for dogs. If they applied these rules to people though, they'd be sued in a millisecond.
If you're someone that pretends that your dog is a service dog so they can come around with you for the day. You may want to think twice about doing that.
Before you call this guy a "hero" for what he did, consider for a moment that whatever this guy's likely motive was you can be sure it had nothing to do with wanting to "help" the animals.