My recommenders copied letters from online I'm an international student applying for college in the US. I asked subject teachers from my current school to write me recommendation letters, specifically telling them not to just copy one from the Internet. I'm using the Common Application for four out of the eight colleges I'm applying to. 

My recommenders submitted their letters to CommonApp and only then did they show their letters to me (which was okay, because I waived my right to review the recommendations) and when I checked online, they had ended up copying 99% of the letter from ones found online.

My question is, will this affect my chances of getting into these colleges? I'm not entirely sure if copying recommendation letters from online counts as plagiarism, and I'm also not sure if colleges check for plagiarism in LORs. Thanks for your clarification!
Yes, it counts as plagiarism on the part of the teacher. There are 2 possibilities if they check the letter and find the plagiarism:
1. the university thinks your teacher copied the letter from an online source. This will make them be highly skeptical of the teacher as an academic and it will probably negatively reflect on you as a consequence. They might think you have worked in an environment where plagiarism is pervasive for example.
2. They think you forged a letter from your teacher by copying one from the internet and sending it in their name. This is of course even worse for your chances.  

Either way, even if the universities don't check all letter for plagiarism,you must consider the possibility that the reader at the university will recognize the letter. Or they might suspect plagiarism after reading it and check this specific letter.
My advice would be: ask for an original letter, but whatever you do, don't send this letter.