Your play leaves you odd-ended and leaves a shot next turn after 66, 54, and 65. Clearing the 7-point leaves a shot only after 61.
When bearing in against the deuce-point, your 7-point will usually cause you more trouble than your 8-point, so when you have a choice you'll often clear the 7 first. This position is actually typical, not unusual.
When you have to play 6s from the bar you end up with guys on the ace and lose flexibility. Clearing the bar prevents that and kills your sixes. As a bonus, the ace puts a spare on the 6 where you need it.