My country is full of pushy salespeople who are asking for a phone number, name or email in scenarios where they are not warranted.
Scenario 1: Cashier at a pizza shop asks for my phone number before billing my purchase.
Scenario 2: I went to view 3 gyms, and after the viewing I told them I will get back to them if I am interested. All three gyms asked for my name and phone number at this point.
Scenario 3: Called a hospital to get the price for their health screening packages. After telling me the prices, they proceeded to ask for my first and last name, presumably to put me in their marketing database.
Scenario 4: While browsing clothes at a store, the store manager asks for my Whatsapp number so I could view status updates about any new products.
These businesses often spam or sell the name and phone number combinations to other spammers who can get around the do not call registry by using a new number each time.
I want to keep my privacy and avoid spam without having to maintain a second number.
Most of these times I have caved in and given them my number as I cannot think of a reasonable excuse. I thought about saying "I don't have a phone" but that seems suspect as I carry my phone with me. How can I tactfully decline giving my number without being rude or awkward?