Bad attitude from thw manager

I went to Mug and Bean Wonderpark on Tuesday morning the 21st of August. Just an hour after I've been there sitting busy with my assignment note the manager approached me and told me that me ordering only rooiboss and occupying her table space is a loss and that the her stuff is not benefiting anything. I felt disrespected buy wat she said.... She undermined me. I then asked her to kindly send bd me an email explaining that I'm not allowed to come in her restaurant and order a cup of tea while I'm busy with my work and she rudely kept me waiting. According to her only customers who buy food are important than those of us who r there for tea or a cup of coffee. She went on to tell me that the last time I waa visiting the restaurant I ordered a slice of cake meaning she is busy monitoring what I order and it made me so uncomfortable.