Barman rude and threatened us to not come back

I have been to Amsterdam Action Bar before and had a good experience. Seeing it was New Years Eve and my friends and I happened to pass the bar, we wanted to pop in for drinks as the new year vibe seemed good. We stopped and ordered about R200 worth of shots to start off.<br> The first bartender was really friendly. He was bald with a cap and made us feel really welcome.<br> However, whilst paying for the first round, the second bartender, who wasn't bald and had a longer face, told us that bartenders work on tips and that if WE DO NOT TIP, THEN THEY WILL NOT SERVE US AGAIN. To which I responded : \I am aware that bartenders work on tips as I've been to many bars before. And if you don't serve us then we won't buy here again". He said \""Then don't come here\"". He repeated this several times in a very condescending tone. He basically assumed that we weren't going to tip (which was going to be first round of drinks) and said that we were not welcome anymore. It was embarrassing as it was stated loudly in front of other customers. I am disgusted at how my party was treated. I felt personally attacked. We tipped and left. I have a bad view of Amsterdam and trust it will be handled further."""