Coffee 4 You - Horrible Customer Service

We went to this coffee shop today March 19th 2017 and we received horrendous customer service. We bought a $5 coffee, sat down to use their wifi, and began to eat sandwiches that we packed earlier in the day. After about 5 minutes a man named Ragnus, approached our table and aggressively told us to leave because we were not allowed to bring outside food into the coffee shop. We said we are sorry and didn't know because there are no signs that specify this, but also said we would pack up our things and leave. However, Ragnus, would not accept this as an answer and continued to get more and more aggressive telling us to leave. We again repeated that we needed a minute to gather our things and put our jackets on. Ragnus still continued to tell us to leave. Then, he grabbed my cappuccino and sloppily poured it into a to go cup, spilling some of it on the table, very close to my phone and gives. He did not apologize, but continued to command us to leave. Again, this was a horrible customer service experience, one that came as a surprise considering how polite and hospitable everyone in Iceland has been up until this point.