Most Helpful Girl
Being thrifty doesn't necessarily mean being frumpy.
I mean, a ton of girls with lots of money frequent thrift stores because you can find gems of clothing there which you wouldn't stand a chance finding in regular stores. You just need to spend a bit more time in there rooting through stuff and you'll find something which will look great on you; and a lot of classic things in there too.
People buy things in fashion, and get rid of things when a new trend comes along, and some of these 'out' trends are pretty timeless and can look great.