Municipalities don't call them "quotas"; they refer to parking ticket issuance as "performance targets".
According to our sources, if agents do not write enough tickets municipalites will discipline the Agent for lack of productivity. This could result in demotions, transfers to more dangerous areas and moving the Agents to foot patrol from vehicle patrol. In other words they lose the keys to their vehicle and have to walk. There is no greater incentive for agents to write summonses than a transfer to foot patrol. This is why you, the person trying to find somewhere to park, pays the price!