Maybe. Unfortunately, there are too many variables (including specifics of any would-be point system and the time value of money to each of us) to definitively calculate which is better. I prefer getting my discount in the here and now, on what I need/want today, rather than a potential future savings on something I may never buy. With a percentage discount, I know exactly what I'm getting and I leave nothing "on the table." With a point system, you frequently have some amount of accumulating (i.e., unclaimed) discount that requires additional purchase(s) to receive.
In the end, Dylan asked what we prefer. Obviously, each of us is free to offer an opinion. Ours happen to differ.