What amuses me most about those stores is when major designer stores literally COPY the goods you can find in the surplus stores.
For example, Banana Republic had an exact replica of a grey Swiss wool army coat, right down to the buttons with the Swiss cross on them. $495.
A REAL one, made better, was $25 at a surplus store.
M-65 field jackets are also found as copies in mall stores, at over $200, but they're generally cheap cotton/poly from China and not actual ripstop material. It amuses me to no end. Can dress in the latest military-derived styles, for pennies on the dollar, with the real thing...which is made better than the copies!