I see the reasoning behind this but you would think the morons at JQ would give you the bad news before delivering the "trust me, we are Jetstar and we are here to help" type spin which reads:
Check in online to be greeted by "Welcome to Jetstar's Web check-in service, designed to save you time."
This is followed immediately by:
"Web Check-in is not available for your booking as one or more passengers are seated in an Exit row and not eligible for Web check-in. It is a Safety requirement that customers seated in an Exit row physically check in at the airport counter, in order for staff to assess the suitability for these seats (the minimum criteria is listed at the time of booking)."
Idiots. Gold medal for consistency. You'd tolerate that from any other airline but this mob seems to excel in being excruciatingly flawed at each and every turn. Simple irritations become yet another nail in their coffin.