If all rides offered are good paying rides, there's no need to turn them down. Premium rides are more likely to be good paying rides than Standard rides.
I was at the gas station, about to get gas, when a male walked up to my vehicle between the driver door and the gas pump and offered to pay for my gas. The deal was, I give him half of what I'm going to pay and he will cover the full amount. I told him I was using a card, and he said that he has a business account to accept payments. I immediately declined and handled my own transaction out of annoyance of being bothered, but it occured to me later that this was an attempt to get my card information through the payment transaction, potentially with the intent to clone my card. Even on the off chance that this was some altruistic act of kindness, why half off and not just cover the full amount?
My issue with this system is that it isn't an impressive amount to call a bonus. However, they've made it so that you'll look silly for complaining about it because you're going to work towards your goal regardless, so why get mad at -anything- extra being thrown on top of the goal you're already working toward?