Do tickets purchased at aaa get replaced if lost like Disney tix bought direct from Disney. We once lost a ticket and they replaced it. AAA park hopper tickets are about $8 cheaper but not worth it if not protected.
The tickets that I’ve bought from 3rd parties are a card with a bar code, and you type that number into My Disney Experience, and associate it with a person in your party. Then, you can’t lose them. They’re linked to your account.
I don’t know how AAA tickets work, but I presume it’s similar. And you want to connect your tickets to MDE before your trip, so you can make FastPass reservations.
I have never really seen a huge amount off WDW tickets, and I shopped around for a year or so while planning my next trip.
What IS the definition of a third party pticket. I would have thought that AAA was a second party ticket.
The first 2 parties are you and Disney. So, anybody else is a third party 
The tickets I got from Undercover Tourist 2 years ago were the same RFID cards that I got directly from Disney for Mickey’s Not-So-Scary Halloween party, except that they had different info on the back. The party tickets had a date and the name of the person who the ticket was for, because they are only good on a certain date. The UT tickets said how many days and adult or child.
UT is an authorized reseller of official WDW tickets, and for some combinations, you can save a few bucks per ticket (I suspect that AAA is, too, if the discount is only $8). I think there are shady places that purport to sell tickets for much less than Disney, but I don’t think anybody here would advise you to buy from them.
When you buy from AAA, you get a card that’s brand new and you can link it to your account. It’s not one of those resellers that buys extra days off people. I’ve had no troubles with my cards working, although, I never lost one, either.
If its linked and been activated ie used to get into park wdw will replace. ( happened to my sis) If its linked but lost prior to first use its more difficult and wdw might make you contact your ticket seller for cancellation/ replacement which poses a problem if it is linked.
The advice I’ve read is to take a good, clear picture of the back of each card, to facilitate replacement. I’ve never lost a card, so I don’t know if that would help or not.