This would apply to all BitAssets.
This would reinforce the peg because the "best of all worlds" trading strategy is:
Short 100 USD
Hold 100 USD
if BTSX goes up, borrow 100 USD on your credit card, and cover at a profit, pay off your credit card with 0% interest.. keep the profit.
if BTSX goes down, Cover with 100 USD and keep the rewards.
Thus there will be heavy demand to enter this position, but the only way to enter this position is to be the "first in line to short" which means paying a high initial shorting fee *AND* that the peg is holding at parity.
Thus I believe this rewards program will make the peg stick no lower than the feed price.