In this case, you have someone pay a small parking meter fee and then they sit in the public spot waiting for someone to offer them more than their original met

In this case, you have someone pay a small parking meter fee and then they sit in the public spot waiting for someone to offer them more than their original meter fee. This is very similar to domain name registration. You have someone pay a small registration fee (~$12) to register a domain and then they sit on that domain waiting for someone to pay them substantially more for it. If it is ethical for a domain name market to work this way, why is a parking meter market different?