Sorry your cruise did not go as you thought it would. The service charge, internet charges, soda and juice charges and the towel charges are all pretty standard on Carnival, Royal Caribbean, Holland America, NCL, Princess and Celebrity that I have been on. These are standard things on the standard Cruise lines in the last 20 years I have been cruising.
You Cruised on MSC, it is a bargain line and not known for the food. I have read some reviews that like the food on MSC and others that say it is bad, Same as reviews on NCL and Carnival. When you book a cheap cruise you should not have expectations set to high.
Before you do another cruise I would suggest you do some research on the cruise lines web site, on cruise review sites like this one and ask your travel agent a lot of questions so you know what your in for. I would also recommend that you do some research on your ports so you know what you want to do in each port. Try the Ship Mate app for your smart phone and there you can go the the forum to chat with guest that have been on that line before. It also has an area with non-ship excursions and a area where travelers recommend restaurants, stores to shop in and places to go and see.
With some research you can have a great cruise vacation.
I do not have any vested interest in any cruise line so you can not say that to me as you said in your above comment to others. I actually would prefer cruising to not be so popular so I could get lower rates and better cabins.