Often you can see on twitter or Facebook plugs and recomendations (sometimes it's self-promotion) of 99 cents books. Buy, it's cheap! - a recomendations call. And yes, it is really cheap - a book with under-dollar price. In Russia even with 600-800 month income you can afford 30-40 ebooks every month. And it's only for 30-40 dollars.
But here is one not so little problem. Amazon, most popular online ebook retailer, charges two extra bucks if you buy ebook from outside of US of A. Yeah, if you live in Europe, Africa or South America, you must pay for 99 cents book $2, 99, not 0,99.
Do the math. You have the same 30-40 bucks and with 2,99 price you can buy only 10-13 books. And if you wanna buy 30 ebooks, you have to pay 90 bucks. And in Russia it's not that cheap.
Now you have 3 options:
1) buy less books
2) try to cheat Amazon, but it's illegal and not too simple.
2) use other retailers, such as Smashwords, they don't charge extra money. But these retailers don't have such selection of books that has Amazon.
So if you a writer, place your ebook not only on Amazon, think about your foreign readers. And don't shout "It's cheap". It's cheap, but not for all.