chapotraphouse

Like am I going to have to declare that I'm carrying an $18 t-shirt and 3 euros in cash if I'm returning from a trip? And customs is going to process that?

That would be a pretty funny outcome. A lot of countries already have awkward and inconsistently applied enforcement for people who are simply traveling with expensive equipment that is subject to customs duties. Imagine if the distinction between market goods and personal property was simply eliminated, and everyone had to pay duties on everything they brought into the country.