25-cent video poker should be worth about $40 your first day playing if you were to play an eight hour shift. That can easily double after a few weeks of practice. Then you can move up to $1, $2, and higher. Problem with that is I can't handle playing machines for more than 30 minutes at a time.
With a $40,000 bankroll (just two years of minimum wage salaries) blackjack should be worth about $60 per hour. Problem here is that to stay under the radar you can't play very long sessions. Show your max bet once and get out.
In sports, picking 53% winners and 3 games per day, it would require close to a $350,000 bankroll to earn $100 per day. Picking 6 games per day and winning 54% would only require only around $35,000 to earn $100 per day.
It can definitely be done, but the hourly rate probably won't be too good. Most of us would be better off earn $50 while cutting way back on amount of time required