Although on the whole I try to be economical and thrifty (often fancy words for "cheap"), there are a few luxuries I purchase for myself that literally make no logical sense. Books are one of these, of course - not that books are illogical of course, only the rather sheer quantity I own and continue to procure.
Another is shaving cream.
Many many years ago - good heavens, looking back I see it was 11! - I wrote a post on A Good Shave. I had converted over to using soap in a bowl and a bristle brush years before that, mostly originally out of an obstinate need to be different and vaguely British (while everyone uses the same cream, for some reason I associate it with 19th Century Britain). And then at some point, I took a risk (most likely based on some article I read) and bought shaving cream.
It can be said - and righteously so - that in an age of increasing expenses and instability, the concept of spending a rather foolish amount of money on something that can be procured more cheaply is silly at best and foolish at worst.
If practiced for every item we buy, I agree. If practiced in small ways, I do not.
We can always purchase things that are effectively the cheapest and the lowest common denominator, and if practiced over time, we will save money. What we will not save and sometimes sacrifice is the enjoyment of very simple pleasures. Something like whipping up a shave in the morning that is from a bowl and brush instead of a can is indeed a very simple pleasure for a practice millions do anyway; the difference is that something simple like shaving cream turns a daily task into something of a pleasure.