Are Exclusively breastfed babies suppose to sleep through the night?

I am exclusively breastfeeding and my LO (almost 6 months now) still wakes up 1-2 times a night to feed, between 7:30p to 7:30a (usually between 12-5am he would stir). I've been fine with it as I'd be engorged and can't sleep anyway.

However, many of my friends had their babies weaned off the early AM feeding when they were 2-3 months, but they did a mix of formula and breast milk. Even our pediatrician told me to ignore him at night.

What is your experience? What would you do?