Bitconnect does pay
The risk of Bitconnect right now is that the website will shut down and we all lose our principals. I think this risk becomes less and less over time as the community gets bigger. Also because the tokens are on a blockchain there is some magic which is possible in the case the website is shutdown depending on whether or not the site operators are wise enough to back it up. If it is shut down it will likely be due to the authorities shutting it down for being an unregulated exchange and not because of any sort of scam or Ponzi Scheme scenario.
If Bitconnect handles the situation right then the site can last as long as Steem. Because they have their own token, and the blockchain isn't going anywhere, the only thing which can be lost are the Bitcoins you used to buy the BCC tokens in the first place. Those Bitcoins keep going up in price, but that is what could be lost.
Some misconceptions about Bitconnect are that they promise daily interest of 1%. They do not promise any set in stone interest rate. The only promise they make is to do capital release at a certain date and the interest is based on volatility software. The interest payments could stop or go to 0% at some point but as long as Bitconnect remains profitable then this will not happen.
I do not think Bitconnect is a security if there actually is a trading bot. I don't think it is a Ponzi Scheme. It may be a Pyramid or HYIP but so is Bitcoin which is also a pyramid with the old wallets earning 10,000% return vs fiat. The risk of buying and holding Bitcoin is similar to the risk of buying and holding BCC.
What Bitconnect can do in the future to take over? All they need to do is figure out ways to decentralize their revenue stream so that it doesn't only come from one website. This way the central point of failure is removed and if revenue streams come from many different layers or sources then even if the exchange service fails or shuts down the interest payments continue. This would mean Bitconnect would have to expand far beyond what is in the current roadmap.
What about the Bitconnect stores? I think a key sign for whether or not Bitconnect has staying power will be whether or not we see the launch of these stores. Once we begin seeing Bitconnect stores, and if by some means interest payments are a result from some fees from these stores, then you will have a very decentralized Bitconnect which likely will not be stoppable unless every store all around the world is shut down.
What would be sold by the affiliates in these stores though?