Most continental breakfasts I've seen run from 6-9AM and I've always interpreted it as a sneaky tactic hotels use to usher guests quickly out the door given that standard checkout time is usually 11AM.
It's not sneaky, most would happily tell you it's a combination of that plus not wasting food for the few people who would normally meander out at the crack of noon
There are two types of hotels: those who serve early breakfasts because most of their clients are early birds, and all inclusives where most of the clients are night owls. You're just staying at the wrong type of hotel.
Maybe I'm in a fortunate position. But I have never been to a place where breakfast was as good as an average cafe.
From my experience: If Hotel A and Hotel B were pretty identical the same but for $20 more, you get all you can eat breakfast, don't bother. Just buy breakfast.