If it is 2-3% profitable, it is 2-3% profitable, the amount of capital used is irrelevant.
If people want to trade their 0.5BTC to make 0.0002BTC, that is still guaranteed profit, there is not need to have too much capital.
Often the amounts that can be traded at the ARB price are also very limited, so again, capital wouldn't help.
youve got a point, profit is profit; i may have used poor wording here, when i said profit i meant something along the lines of a substantial portion of one's income. also I dont use exchanges very often if at all, so I was not aware the trading limits would restrict arbitrage so much