First, like your dentist and GP, your lawyer is busy helping others. Appointments are mutually beneficial because you get the lawyer's time focused on your needs.
But more important legally is that the Law Society has pre-requisites. Lawyers must first ID their clients for 2 reasons: like banks to prevent fraud, and to complete a Conflict Check which also requires the name of the opposing party. There is a saying: "once a client, always a client" because lawyers are not allowed to ever act against a client (unless they consent). Thus every time a new client contacts a lawyer, the lawyer must first check their database for the names of both the prospective client and the opposing party to confirm there is no conflict = to confirm that the lawyer will not be helping someone in conflict with an existing client.
Last but not least, is the reality that the business expenses for a law firm are very high and time is what they sell. For the same reason the receptionist for your dentist and doctors confirms your method of payment, law firms need their time paid or else their rent and staff cannot be paid. In addition to all the normal business expenses, just the Provincial license and insurance fees for one lawyer are thousands of dollars.
Like all service businesses, lawyers want to help - our job is to help solve problems and disputes for our community, both business and personal needs. We Can Help you too!