There's actually quite a few. Can't think of them all, but the idea of things like making your own shampoo concoction is overkill to me. You can get a 39oz bottle of shampoo for like $7.50 US. Bought a bottle in January of this year and still have more than half the bottle left.

Just seems like the effort and cost savings aren't worth it to me for something like this. Plus it's questionable if it even works as good.

Basically though, I think people confuse cheap with frugal. Frugal is being about getting the bang for the buck, not depriving ones self for the sake of saving a few dollars. Mobile phones are a good example. Is there really a need to get a $1000 flagship phone when I can get a $200 lesser name phone that can do all the same things as the top tier one can? Sure, the photos might not be as high quality, but they're way good enough for every day use.