Chariot Race + City Quarter (debt?)

[GrantedHanted]

Game #98748584, rated

Might not be a bug, turn 12, City Quarter revealed by chariot race against a copper, point and coin awarded.  My understanding is debt cards matched against coin cards lead to a draw and the chariot race would gain no benefit if they revealed a CQ and I reveal a copper.  Not sure if there's a different consideration for cards worth 0. 

[dane]

0coin+8debt (City Quarter) is more than 0coin+0debt (e.g. Copper, Curse), but is indeterminate against all cards with a non-zero coin or potion cost with one exception: it's less than 8coin+8debt (Fortune).