Well that sounds like a right pickle. Generally whatever entity is in charge of providing parking would be the one to bother to find a solution. If that's the business, reach out to a manager or other decision maker, if that's the municipality they of course can be reached and usually love a low cost high impact change they can make at the request of a citizen. If that's a shopping center thats probably still a manageable process to notify them of the demand. All of the above are financially incentivized to provide adequate customer parking, and customers leaving bikes in the walkway would indicate a strong customer demand for more bike parking