Not sure what you mean by standard sized. Take-out cups are at a minimum 8 oz. If you mean the ones that come with dinnerware that are 6 oz, I would have to say when you're having dinner, it's easy to refill the cup if you want more coffee.
They are for people, like me, who refuse to drink coffee that isn't very very hot. I use a one-cup coffee brewer at home. I keep one upstairs too and that little cheap thing will only accommodate a very short cup....probably about 8 oz. I generally use a 12 oz. mug though.
Yes, but I tend to slush it when I'm going up the stairs. If I'm working upstairs I sometimes make a cup up there. It's just a little one-cup maker that sits on the freezer in the storage closet. I used to always use travel mugs but I really don't like to put the plastic on my lips. I know. Quirky.
This is the sort of question that makes me wonder what you were trying to ask.
The standard size coffee mug holds ten ounces of coffee and the walls are quite thick. That is primarily so they can stand a lot of rough handling without breaking, and there is the incidental benefit of holding the heat better.
Mugs for home use are not that thick and not always ceramic, but are otherwise the same.
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SpunkySenior 