Huh?

I had to go out to run a time-sensitive errand so I got that out of the way and then went over to Sainsbury's to get my festive shopping. We have a weather warning in force and there was a torrential downpour as I headed across town - the drains were overwhelmed and in a number of places the water was fountaining from the manhole covers to a height of a couple of feet, drivers were all over the place to avoid the fountains, the pools of standing water, and fast-flowing streams. 

It's always magical visiting shops at this time of year, isn't it? Families of people who have clearly never visited a supermarket and who have to stop in the middle of every aisle to gaze in wonder at the plentitude surrounding them. From their central viewpoint they then have to read the label on each and every product as though, somewhere, they might find the Holy Grail. People who stop suddenly and start reversing without glancing behind them such that they are prostrate across one's trolley and glaring as though the fault was mine alone. Oh, how we laughed.

And now the question from the subject line - in the name of all that's holy, how would this little packet serve 6?