I believe you are precisely right in pinpointing McVay's thinking.

Two things to consider:
1. The rules really benefit the passing game so it seems counter intuitive to not take advantage of that. Similarly, it makes it harder on the defense, so asking them to shut down an offense for 60 minutes might be difficult.

2. The more you handle the ball on offense, the increased chance of a turnover, especially with a QB who has been known to fumble when sacked.