Because Raonic is a top 13 in the world type of player and Qurrey isn't anywhere near that.
I had Querrey too and I'm glad we won but thats why
Ranking doesnt mean shit these days. Raonic is not any good on grass and it shows. Querrey isnt grass-master either , but at least he has lot of experience on surface, won Queens couple of years ago, was in second week of Wimby.