If villain is unknown then calling isn't such a bad idea. He could easily be making this play a-8 of clubs, 7-8, and at this level people will make this play with 10-10 thru k-k as well.

At PP 25NL it is hard to fold a-a after the flop and have it be the right decision enough for the fold to be correct.

I call and probably lose more than I win, but win enough for it to be slightly +EV