Never saw such a rule on a casino site (and I have used a lot of them) and this is just ridiculous. I can understand that you would need to make a valid bet if you received "free" money from a free bet or a promotion but a 100$ bet is quite extreme. If they continue to create these rules, there will not be a lot of players left to play on the site lol.
Indeed. Besides that, the free money is not too high compared to what we use for bets so I do not think it attracts the players to spend their money to chase the "free" money. Maybe they will still play gambling on that site but not for the free money as they do not have an intention to get that because they can get it from other places. They should change these rules because that will not make their members comfortable with that but that will be up to them if they still want to use that rules.