Personally I won't wear anything unless it's a brand name! But, they came from thrift stores. I shop regularly, and on occassion that perfect dress is there and home it goes with me. Once on Celebrity my floor gown that was black and with sequins, was $2 as it was half price. On Sunday I'm on Carnival with my other "new" $3 gown and actually $1 new shoes I snagged at a yard sale last week. I can keep up with the Jones's and have money to spend on building memories.
Just be a little dressy on formal nights and you'll be fine.