Almost every prof I know uses a template for recommendation letters, and adds a paragraph or two specific to the student. I'm not surprised a about the reuse of a paragraph and similar wording.
Remember, the purpose of a letter of recommendation is to make the case that you are a good student, and will be a dedicated, ethical researcher, not to introduce new research or new ideas. No one could be harmed by a plagiarized recommendation, so long as the recommendation accurately reflects the opinion of the "recommend-er."