I don't think it needs to be outlawed, just better regulated. Say If you are paying 1k a year for a private parking space and you are turning up at home everyday to find someone in your spot and nothing that you do seems to help then a financial threat on the illegal parkers is ideal with correct signage and following precedure. The problem lies with cases such as this topic, where the actual user of the space doesn't want to prosecute but can do nothing about it as the clamping company are operating on behalf of their own company, not the client.
Clamp his car.
But for the purest engine experience, displacement has no replacement. All other methods are simply attempts to artificially recreate the benefits of displacement.
ebola is more effective i here