word meaning - Does 'breakfast' in "Let's have breakfast" denote an activity or a collection of edible items?

Let's have breakfast.

In this sentence, how would a native speaker comprehend the meaning of "breakfast"? Will he think of it as an activity, or as a collection of food items?

The question is inspired by this comment by GoDucks:

I am confused as to the designation of breakfast as an abstract noun. I mean can't we see, taste, touch, smell, hear breakfast? (The same for coffee, which I don't think is abstract.)

If breakfast here is closer to "activity", would there be a difference in comprehension between have breakfast and

Let's eat breakfast.

Answer

Breakfast is the meal one eats in the morning (before noon), usually after waking up, and may consist of different foods depending on culture. Some eateries will serve an all day breakfast, and this first meal of the day when taken late might be referred to as brunch (breakfast and lunch).

Breakfast comes from the phrase to break (one's) fast.

American breakfasts will typically involve any or all of coffee, juice(s), eggs, cereal, bacon, pancakes, sausages, toast possibly with butter and jelly, waffles, maple syrup, hash browns, home fries, doughnuts, muffins, fruit, or yogurt. Southern tastes may include servings of hominy grits with butter or gravy, buttermilk biscuits, anything with pecans and a purpose made breakfast casserole, y'all hurry back! For undergraduates at university cold pizza is not uncommon.

A full English breakfast or fry-up classically consists of eggs, sausage, bacon rashers, potato triangle, fried mushrooms, baked beans, fried tomatoes. Inclusion of black pudding, white pudding, or haggis would make it Scottish.

Hungry yet?

Let's have breakfast
We're eating breakfast
Let's breakfast together
Let's do breakfast (when it was fashionable to say such a thing)

all refer to the meal and activity.

I would disagree that breakfast can not be seen or smelled. In the morning, if one smells eggs cooking or bacon frying or coffee being made, most people will think

It's breakfast time!
Breakfast is being cooked
Breakfast is being served

Breakfast is both the name of the activity and a collection of items

For breakfast we had eggs and bacon
We breakfasted on eggs and bacon
We had the usual breakfast

There is no difference in meaning between

Let's have breakfast
Let's eat breakfast

When you are having breakfast, you will be eating your breakfast.

Under duress, one might emphasise the eating over the having

I have not eaten for days

I need to eat breakfast before I die of starvation!

I would like to have some breakfast before I die of starvation!

the latter is more genteel and not quite the same in urgency

For those interested, scrambled eggs on the International Space Station here
(hopefully not blocked outside UK)