I have one daughter who loves to eat PB just by itself. I'll scoop it out of the jar with a knife and send it in her lunch. i use a small, square plastic container. I found the containers 8 for about $3 somewhere. She looses the lids often, probably in the garbage can. But, for that price, I can handle it. I figure I spend about $.10 each for this snack. Compared to $.75 or so for the pre-packaged PB. Plus, throwing out all that extra packaging makes me cringe.
I am busy. 3 little ones 5 and under. 2 in school. I teach 2x's a week. Remodeling a house. So, I do use some convenience items. I buy gas wherever is closest, don't have time to drive to the cheapest place. I hire contractors instead of do jobs we could do ourselves because our time is worth more than we pay them.
But, there are some things that take so little time that I love to do to save money. I make my own yogurt. I package my own peanut butter into little containers. I pack my girls' lunches and cook ours at home. I cook dinner from scratch most nights.
i guess it's all how each individual person chooses to look at it through their own eyes in their own family life.