The airline industry has been so successful at nickel-and-diming its customers with fees for everything from checked bags to priority boarding, the hotel industry is now following suit. 

Hotels will rake in a whopping $2.25 billion in revenue from add-on fees this year -- an increase of 6 percent from 2013 and nearly double from a decade ago, reports the Associated Press. And about half of the increase is from the addition of new types of fees and the increase in amounts for existing fees. 

The figures come from a study released by Bjorn Hanson, a professor at New York University's hospitality school. 

Here are a few of the most outrageous fees some hotels are charging:

  • Storing luggage for a few hours after check-out time: $1 or $2 per bag
  • In-room safes: $1.50 a night
  • Internet access: $10 to $25 a night 
  • Personal use fee for storing your own water bottle or drink in hotel fridge: $25 
  • Early check-in/late check-out fee: $30 
  • Receiving or sending packages for guests: Anywhere between $1 and $25 
  • Minbar re-stocking fee: 18% of items bought 

And that's just a small sample. Hotels are getting more creative when it comes to dreaming up new fees. So is there any way to fight back? 

Bjorn suggests reading the fine print on your hotel bill. And while fewer hotels will waive such fees upon request, it's worth it to ask -- especially if you weren't told about it in advance. Better yet, call your hotel ahead of time to find out what fees might apply to your stay. If you're searching for a hotel, try booking site, which includes information on taxes, resort fees, parking and wi-fi in its search results. 

Be sure to ask about fees when you check in, as well. Some hotels will charge a "resort fee" for access to the fitness center or other services. If you don't plan on using any of them, let the hotel know and ask for the fee to be waived. 

Finally, if you're a member of a hotel loyalty program, use it. Many offer fee waivers for their members. Kimpton's rewards program, for example, offers free wi-fi to its members.