aren't we just enriching these people? This is why I hate using Bitcoin to gamble today, it's a waste of valuable asset.
Did these people ask or pleased with you to enrich them? 
(just being sarcastic tho), but you might not have held the 1 Bitcoin till it gets to today's price or value. Honestly, if you had not spend your 1 Bitcoin in freebitco, would you be able to hold it till now? I am guessing that you would have sold it before now. Whether people are still gambling or betting with Bitcoin or not, it doesn't stop the casino from being richer, gamblers are still enriching the casinos irrespective of any currency they are using (be it Bitcoin, fiat, cryptocurrencies) . 1 BTC at the time doesn't worth much, it's not as if I won't survive without it, and moreover this is just a discussion, if these casinos held the Bitcoin for years now they would have made 20 times their money already and if gambler hold their Bitcoin instead and maybe use Fiat they would have been rewarded right now.
You said be it Bitcoin or Fiat, are they the same? One adds value like gold and the other depreciate in time, I remember someone created a post on this section that Fiats are better spend on gambling than keeping them in the banks, what do you say about this? Stop trying to prove what's not needed to be proved.