Don't mean to be insulting, but you alluded to it in your question. Yes, it is absurd to spend 100 dollars on cabling for a cheap 100 dollar DVD player, IMO. Cables, while they will have an impact on the performance if they are total crap, should not have to cost much.
I spent about $130 on 30 feet of professional belden RGBhv cabling, and you can't really do better than that. However, I am feeding a projector that cost at least ten times that much when new, via an HTPC with very high quality performance. (edit: apparently I can't do basic math, since 10x $130 is just 1,300. Lol. I meant 100x, another zero was necessary

. )
That you spent 100 dollars for probably a short length of what is probably just component video cables, tells me you were very much ripped off.