I don't think that it's normal at any school, but it is often an option. Unlike Carribean schools, who really don't care whether or not you pass (they have 400 more people with good credit waiting for your seat), US schools actually want you to succeed. Most schools have a way to help you through if you struggle a little at the beginning. LECOM, for instance, has a remediation program where you are offered a chance to study and pass an exam after you fail a course or PBL module. If you make 70% or better ,then you can continue. You have to pay extra for it, but it's still better than outright dismissal. If you don't pass the remediation exam, then the SPG committee will either recommend dismissal from the college or repetition of the school year.
Note that passing the remediation exam will give you a grade of C, but an asterisk will be placed on your transcript. Yet, that's still better than outright failure and dismissal. How often does it happen? I really couldn't tell you...but it does sometimes.