So I went and took a look at the game reports to check this out and see if this was more widespread than just a couple of players (there were actually 2 Blues ECNL players mentioned by name in this link, but I only saw the one when I posted the question). Turns out that neither of the two Blues players played nor were rostered with Blues for at least the first game.
I decided to hunt around just out of curiosity and see which clubs played their regular line-ups for the showcase and which brought in a bunch of non-rostered players. I only checked out about 4-5 SoCal clubs, and it looked like most of them played their usual regular season DA line-ups with usually just one or two DP players (often youngers or players from their DPL teams).
However, I noticed that LA Premier had 5 girls from their 2000 DA team playing DOWN in the showcase for the 01/02 team. I didn't bother to look up the rules. At first I thought it must be a typo or maybe they are trying out that "bio-banding" thing. But after reading more game reports, I'm assuming this must be ok by the showcase rules, because I also found a 2000 player who played for Surf and one from another club from the east. Ok. But
5?? Half their team were playing down nearly two age groups? What about that 02 DPL team, LA Premier?? If you were short players for the tourney, didn't a few more of those '02 or '01 DPL players earn the right to play? Isn't that how this was supposed to work? If I had a kid who suffered through the DPL sales pitch and stuck through the year and then didn't get a chance to play in the showcase because you brought half your older team down . . . well, I'd be pissed. Then again, maybe USSDA told LAPFC to do this so they didn't get totally embarrassed. After all, with half their 2000 DA roster playing 01/02's, they've been able to keep their goal differential to a respectable -4.
Maybe I'm missing something. It seems like maybe the logic was since there is no "showcase" event for the oldest age group, the powers that be were ok letting some of those players play in front of college coaches by playing down, but that sure seems weird.