As far as I know, prices in the caribbean are in US dollars, while cruises in and around Europe are in Euro. Here's what the website has on tipping: Tipping and Gratuity Information
At MSC Cruises we recognize that exceptional service is the most important aspect of your cruise experience. As our guest it is our goal to make sure you receive the finest in personal service.
Since you will meet many members of our staff in a variety of locations throughout your cruise, we have made it convenient for you to reward the excellent service you receive. A gratuity of $12.00 per guest per day will be added to your cashless account on a daily basis (children under 18 sharing a stateroom with 2 adults, $6.00 per day.) This gratuity will be shared by your Maitre d’ and his assistants, your waiter and busboys, buffet staff, your stateroom attendant, room service, bellboys. This is of course discretionary and should you wish to make adjustments you may do so by contacting the guest reception desk at any point during your cruise. Separately, a gratuity on all bar checks for your servers is included in the price of your drinks.
Casino dealers and spa personnel do not share in this charge since not all guests utilize these services.
In port terminals, airports, ports of call and on shore excursions, we suggest that you extend gratuities consistent with local customs.