Scotch is a drink not a race of people
No just frugal
'Scotch' is a nickname for whiskey which is made in Scotland. Scottish people are from Scotland.
Yes, "Scotch" should be capitalized when referring to the nationality of people or things from Scotland. For example, "Scotch whisky" or "Scotch tape."
good money savers, conservative spenders
Frugal
When Richard Drew tested his first masking tape in 1925, it was so ineffective that the painter trying it out reportedly threw the product back at him, shouting, "Take this tape back to those Scotch bosses of yours and tell them to put more adhesive on it!" At the time, the term "Scotch" meant anyone who was stingy or cheap; it was born of the stereotype that Scottish people are all of an overly "frugal" mindset. Although Drew improved his masking tape and developed many other functional tapes after that, the name "Scotch" stuck. 3M continues to market their Scotch Brand adhesive products. Over the years, "scotch tape" has itself become a generic term for any roll of (usually transparent or cellophane) tape.
A Scotch-Irish are the people living in Ireland or Britain sharing a similar ancestry.
A person who is NOT frugal is a spendthrift.
A frugal government is a government that is economical
The suffix for "frugal" is "-ity." When adding the suffix "-ity" to the base word "frugal," it changes the word from an adjective describing someone who is economical or thrifty to a noun referring to the quality or state of being frugal. In this case, "frugality" is the noun form derived from the adjective "frugal."
It's the commercialised name for some products which come from Scotland such as, Scotch Tape, Scotch whisky, Scotch broth. Shortened from Scottish (and after a few whiskies most people end up blurring Scottish in to Scot-ch)
she is such a frugal woman that she never bought a car!