Unfortunately some don't understand the pre-board issue. Because SWA doesn't have assigned seating FAR (14 CFR, Part 382.81C) is what is at issue here. Carriers such as SWA, who don't have advanced assignment seating, are required to allow passengers with disabilities, to pre-board and choose the seat(s) that best suit their personal needs. It is taken out of context frequently but technically the Ops Agent shouldn't have let you pre-board before those passengers with disabilities. Their Ops manual specifies this but the intent of the regulation is lost on many at SWA because they don't know the reason behind the rule. If you were to deny someone with a "pre-board disability" to sit in that exit seat then, yes, that's a problem. This issue is brought up frequently but again, no one knows the premise behind the rule.