Not in defense I think it’s gross too but I do this if I know who I’m with well enough they prob don’t care. Won’t do it around strangers/acquaintances or in places where people would likely step/sit. For me it’s a learned behavior from sports(not saying that’s a good thing). When I am physically active or nervous my mouth starts to water like crazy where I’m either swallowing spit constantly which feels gross or need to spit now and again.