Accommodation or Accommodations?

ScottsEnglish

I often read answers from students where they are discussing accommodation.  Apart from it being difficult to spell correctly - 2 c's, 2 m's - students sometimes add an 's' to the word as in this example:

International travelers help a country’s economy when they spend money on accommodations, food and travel.

What's wrong here?  The problem is with the added 's' at the end of accommodation. 

Accommodations is not common in English because accommodation is usually an uncountable noun.  In other words, accommodation is both the singular and the plural form of the word