Has parking been 'decriminalised' in your town, Scylax?
In many areas local councils have taken over control of routine parking enforcement, using either their own staff or contractors to take on the role previously done by traffic wardens. In such areas the police (or traffic wardens acting on behalf of the police) no longer have any powers to deal with parking violations unless, for example, an obstruction is being caused. Parking control services run by local authorities often prove to be self-funding, so perhaps you campaign to get your local council to take over parking matters. (If they've already done so then ask them why they're not using their powers to their full extent).
My two local towns have different approaches:
In Ipswich, parking has been decriminalised and the local authority employs (extremely active!) staff to look after parking matters. The system seems to work well there.
In Stowmarket, Mid-Suffolk District Council has chosen not to decriminalise parking violations. However Suffolk Police employ PCSOs with 'Traffic' flashes on their shoulders, specifically to look after parking matters (while also performing other PCSO duties when required). Again the system seem to work well.
Find out who is responsible for parking matters in your area (the police or the local authority) and then campaign, through your local councillors, for some improvements.