Yeah, its rly hard to reward people for being on site , for chating and all that, and not make some other people abuse it. There is no perfect system sadly .
The trick is to reward the behaviours that you actually want.
You think you want people chatting, because that makes the site look busy and attracts players, but what you really want is for people to bet.
If you reward people for chatting, they'll find a way of automating it, so you achieve your intermediate goal: "get people chatting", but not the real goal: "get people betting".
You need the incentive to target "get people betting". So you base your level system on the amount they wagered, not the amount they chatted, and "pay" them when they reach various goals. Maybe they get a PD mug, T-shirt, read access to the VIP room, write access to the VIP room, etc. as they climb the levels. Maybe they get a slightly lower house edge depending on their level, whatever. You just need to make sure that you're rewarding the right behaviour.
Also, be precise in what you're targetting. You could have the goal of "get people betting" and so reward people based on the number of bets they make. But they you get an army of bots all betting 0 BTC over and over, and so a more precise goal would be "increase betting volume".
Very true, it's difficult to apply monetary incentives to anything without massive abuse popping up especially in an anonymous setting. Right now users can only level up by wagering and it wouldn't be worth anyone abusing purely for the faucet.
At the end of the day I think it's extremely difficult to provide any sort of suitable reward for veterans/highrollers in an automated manner so we'll have to get more creative.
. Just amazing 
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