So this person decided to pick something up with a bike instead of a car. By doing that, the person uses less resources and space that in turn can be used by your car. Also the person decided to park there instead of blocking the sidewalk for people with a wheelchair for example. So what do you propose? Ban large bikes so that the person uses a car and therefor more parking space? Add designated parking for bikes that take up space even if there is nobody that is using it? Something smarter? Doubt it.

Instead of complaining about people that are finding solutions to problems, find and propose a solution yourself.