Tell us in a little more detail, how much bitcoins was given on average per one-time action and per month?
When I started with faucets rewards were like 500-1500 Satoshi with timer usually between 5 minutes to 1 hour. Maybe it doesn't looks impressive considering Bitcoin value back then. But there was so many faucets and claiming was so easy that it didn't took long to make some significant amount of BTC. Captchas were easy, there weren't many annoying ads - most of faucets were monetised with Google Adsense. Though, I remember already then people were calling it waste of time.
And when I started promoting my referral links, my earnings from faucets were higher than what I was getting from signature campaigns. Managed to get quite a lot referrals. And I can only imagine how much owners of most popular faucet lists were making from referrals because they had thousands of them.