Looking for some advice or wisdom,

At about 17K on the RE92's, I started to get a mild thumping from the tires. The severity was increasing, so I took it into the dealer at about 20K. They took it out and heard the thumping. On the lift they noticed a flat spot on one tire, and out of alignment wear on the rest. On the tire with the flat spot they said the tire "jumped a belt" They suggested new tires and an alignment. They would cover the alignment under warranty. I bought Continental ContiExtremeContact's since I hated the RE92's. At this point everything is great. I love the new tires, winter was coming and I had a blast with the new rubber. The RE92's were like banana peels compared to these.
I bought the Conti's and had Subaru do an alignment. At about 5K I rotated them, and they did not need to balance. After about 7-8K I start hearing a slight thumping. I took them in to the tire shop where I bought them, and they re-balanced them. All four were out of balance. That did not help, I still heard the thump. So Yesterday I went to Subaru to have them take a look. I have about 10K on the tires now. Here was their answer. They found that all four tire were getting worn on the inside edge, but this was normal since the camber is set for performace handling. And the thumping was due to the fact that the tire's tread was not connected on that edge (to help discharge water) and that area (between the treads) was getting wider, thus the thump.

I have been an&l about tire pressure on the new tire's. I was using the 32/29 from the door. I was going to try running them about +5 PSI F/R to see if it would get the tire off the edge a bit.

I need your opinion/help on this.
Is this normal?
Is there someting wrong with the tires?
Is this true about the alignment?
Anyone else have this happen?
Any suggestions?

Thank you all for your help,
CTrexfan