John Gill Commentary Zechariah 7:6

"And when ye eat, and when ye drink, do not ye eat for yourselves, and drink for yourselves?" — Zechariah 7:6 (ASV)

And when you did eat, and when you did drink

Either at common meals, or at their festivals: did you not eat [for yourselves], and drink [for yourselves] ?

merely and only for their own refreshment and pleasure, and not for the glory of God; though that ought to be the principal end in eating and drinking, (1 Corinthians 10:31) .