Anytime ANYONE applies for a credit card, it is subject to approval.
Card companies, banks, lending institutions, web companies -- they all want us to have their credit cards so that we can purchase items, then pay back on time and allow these companies to earn money through INTEREST.
This is not necessarily a bad thing.
What one must do is to read the small print, look over your finances, and - if you happen to be married, talk this over with your spouse - and then decide if you are able to handle the responsibilities that a credit card entails, along with the extra payment. (It may be that the $50 is put on the card, subject to approval. Additionally, you should see if there is a yearly membership fee.)
Remember: you're getting more than just a $50 Reader.
Be smart, purchase wisely.