At least for delivery I think what gig companies have done in places that require an hourly rate is keeping your acceptance rate over a certain percentage per hour and/or have to take a minimum number of orders.

The primary thing that delivery drivers from accepting an order is if the payment (mostly the tip) is too low, if you’re paid by the hour that’s not much of an issue anymore. Other factors that would still be relevant are things like, is it too many miles (gas, wear and tear), is the pickup or delivery in somewhere that isn’t safe or that doesn’t have (free) parking, is it a restaurant that treats drivers rudely, is it taking you too far from where you need to be at a certain time, etc.