On a team desperate for offense, you want to jettison our only hitter who had an OPS over .800? A trade of Renfroe would mean starting Taylor or an all-rookie OF. Taylor, while a superb 4th outfielder, isn't quite on Renfroe's level and is best used as a supplemental option rather than an everyday option as we saw this year. As for the rookies, it is a big leap to assume that they will be able to immediately replicate Renfroe's 2.7 WAR from this year. That just isn't a risk a contending ball-club like the Brewers can afford to take. Overall, getting rid of Renfroe, our best hitter from this year, would be crippling to the offense without any significant outside additions. He is well worth the $11M price tag.
Also, the possibility of Burnes being traded this offseason remains relatively remote. A 10-15% chance, imo.