Think of things long-term. I think the Bills brass knows this upcoming season is going to be rough. Now, they could have traded some 2019 picks and kept some day 2 draft capital, but if they go 5-11 next year then those 2019 picks are going to be early in each round.
It's better in the long run to spend the capital that we already had rather than mortgage the future. We had like 10 picks this year but only 7 picks next year.
Initially I didn't like both trade ups, but after sleeping on it the whole idea makes a lot more sense to me. I think Beane knows exactly what he's doing.