They were more than willing to lose customers for 35 Euro dispute

The ship is new and nice, but the customer service is the worst.  There are lots of hidden charges (food service fee, cabin service fee, etc.) and they would even charge you for a tap water at the bar.   The Internet plan on the ship is a scam.  I bought 250MB Internet Package, for which I was told I could “upgrade anytime” when signing up, but they refused to honor my upgrade because I used up all the data for the previous plan.  Ok, lesson learned, so, I purchased “per minute” plan after my initial 250MB package expired.  But when I reviewed my bill at the end, I noticed that they charged me for the minutes, as well as for another data package plan concurrently.  When I took it up to the Customer Service desk, the lady said that the Internet charge is handled by a system and is automatic, so a mistake is NOT possible.  Then she started to lecture me that Costa cannot be held responsible If a customer mistakenly pushes a wrong button, or forgets to log off.  I happen to be an IT executive so I know exactly how Internet works and how data transmission is not possible after the WiFi is turned off, but she was not willing to budge insisting that system does not lie.  Such an awful experience.  This was my second Costa cruise, and will be the last one.