An admittedly cursory comparison shows that Hoptoad isn't free. That could be reason enough right there.
(edit: beat to it!)
(edit: beat to it!)
Freemium is vastly "superior". Seems fair and of real value. Use this, if you use it so much it costs us "real" money will want to charge you. Use this, if it's all you need awesome, maybe you're just a hobbyist or messing around. But if you're making money and could use these extra features, hey share some of your cash with us.
BTW, someone in here has a trigger happy vote down finger.