這是一個例子
https://www.mainemall.com/en/code-of-conduct.html
Any activity inconsistent with the general purpose of the property, which is shopping, dining, visiting theaters or offices for business purposes
在您的情況,燈柱上面的白色牌子.. 牌子的內容應該是告知這個停車場只容許來購物的客人使用而不是給其他人作為臨時免費停車場,所以你沒有話說....你應該將車停在輕軌車站付費的停車場....
這是相關法律
https://www.portlandoregon.gov/citycode/article/541043
1. The vehicle is parked in violation of a temporary or permanent parking restriction