Bitcoin profit margins aren't like USD profit margins. Bitcoin is throwing out tons of new coins out constantly. When factored as strictly BTC and not USD loans, the opportunity for growth is much larger than your typical USD equivalency. The reward halving will reduce this by a bunch, but its not going away entirely.
This kind of reads like word salad to me. The price of Bitcoins is roughly constant, just volatile. So all it does is add additional risk. Any additional profit potential could equally well be realized with loans in dollars. Just use the dollars to buy Bitcoins, profit with the Bitcoins, sell the Bitcoins to pay back the loans. Even the best arbitragers in the most volatile markets don't make 1%/week.