Good stuff; keep it coming!
As for the vendors, I agree it’s shady that they were allowed to participate in raffles. As for their pricing, well – they’re trying to make a living by buying things for some dollars and selling them for more dollars. They’re primarily targeting the public audience, who (A) probably doesn’t know any better and (B) probably all have whiny kids begging for LEGO at the event, so they’re going to make sales even at inflated prices. They also know some collectors are desperate enough to pay ludicrous amounts for things (see: the $50 sales I keep making of Bilbo Baggins in a blue coat, or Mr. Gold selling for $1000 or more), so why not take their money?
I’ve found that for folks like us, the conventions are not the place to expect fantastic deals, but if you look hard you can find some good ones. Last year, @randomdan found some trans yellow (Blacktron I) quarter canopies for like $5 (they go for $15-20 on Bricklink, I think.) And if you go swoop all of their Space or Castle figs, they’ll give you a discount. Don’t forget that there’s a convenience factor there, too – I may slightly overpay for some minifigs, but I don’t have to pay tax or shipping like I would for a Bricklink order. So yeah, caveat emptor, but depending on your perspective and what you’re looking for, there can be some merit to buying from those folks.