If it seems to good to be true, it probably is.
0.5% chance for 1 bitcoin means 5 mBTC on average per claim, that is 500,000 satoshi. Most faucets pay around 500 satoshi (or anything around that amount), which means 500 sat is the amount that is affordable for the site.
If a site offers 1000 times more, or US$ 2.21 per claim, you can safely assume their advertising doesn't pay that much.

(It is of course possible to get a lot of money for each advertisement, if they are very targeted, for instance a car-website linking to car dealers with visitors who actually buy cars after visiting the site. Faucet-visitors don't care about the advertisements and aren't worth much for advertising agencies.)