I don't think peaople use sugar cubes much any more. I remember them being a staple when my mom served coffee for her guests, back in the day. No one just lounged around the table having mugs, or even to-go cups like we do now. When my mom served coffee, it was a formal, proper sort of deal. The table was set with "company china". There was a cream pitcher, and a sugar bowl. A sugar bowl filled with sugar cubes. Little white squares, hard as chrystal. You used a miniture tongs to get them from the sugar bowl to the coffee cup. They gently slid into that hot, black liquid and dissolved fairly quickly. The cream, nice thick, real cream, not half and half, not little plastic cups with pull off lids, but thick creammy colored cream. Then the spoons began their gentle stirring, gliding back and forth, around and around, blending sugar and cream and coffee into warm coffee flavored sweetness. Of course there was goodie filled plates, too, cookies and korpuu. Korpuu, that cinamonny crunch so loved by the old Finns. You dunked it in your creammy coffee and then it just melted in your mouth. Probably the forunner of cinnamon swirl lattes, or something! Children were not always seated at company coffee, but given cookies at a table somewhere else. If we were included, it was strictly, as "seen but not heard".We kept our eyes open though, keeping count on who used how many sugar cubes in their cup. Something to commiserate over, afterward. The real joy, though, was when the grown ups were at the door saying good byes, we children would be at the coffee table, scooping up a few sugar cubes before mom came back and shooed us away. Oh, I still recall how that sweeetness just slid over my tongue and coated my tastebuds with wild delight. Funny thing though, I drink my coffee black and hot. No creammy, sweet, warm coffee for me.
When I do tea parties for the girls, they love those sugar cubes, too. This is a fun, pretty thing to do, even sweeter..... You can buy the cake decorations at the store, get them from a bakery, or if you do cake decorating, you can make your own flowers. Then just use a dab of royal icing to glue them on the sugar cubes. It looks really special, everyone oohs and aahs, and when you drop it in your tea, (if you don't digress and pop it in your mouth first) the candy will rise to the top and sit there looking beautiful for a minute before it disolves.