I buy games at full price for the social elements of playing a game among others encountering the same fresh experiences. The whole, "did you see that?" or, "how did you kill this boss?" is part of what keeps gaming fun.
More in line with your question, unequivocally Uncharted 4 will be worth full price. Whether $60 is full value will differ between individuals, but a meaty game with fun shooting and an engaging story that the series is known for is worth it for me.