I'm single and used donor sperm, and my RE used ICSI. It seems to be routine for many practices in this area. I think that doctors like it because rather than adding another layer of things that go wrong, ICSI from their perspective adds another layer of control -- they can ensure that every mature egg meets a sperm, and there's no risk of going back to a patient and explaining that for whatever reason, some egg never fertilized.
There have been some studies of ICSI, though, including a major study in the New England Journal of Medicine that came out few months back that indicated a slightly increased risk of certain birth defects among children conceived using ICSI compared to children who were not conceived using that technique. The question still unansswered is whether the manipulation of ICSI causes the increased risk, or was it because of the underlying fertility issue that made ICSI indicated in the first place.
http://articles.latimes.com/2012/may/05/news/la-heb-fertility-treatment-birth-defects-20120505
http://www.nytimes.com/2012/05/15/health/research/birth-defect-risk-higher-with-fertility-treatments-study-shows.html
This study came out when I was already pregnant, so there wasn't any way for me to "undo" the ICSI. I may have used ICSI even had I known about this study because the risk is increased but still small. Unfortunately, we can only go forward based on the best information that we have. If you feel uncomfortable about it, then don't let yourself be pressured into it, is the best advice I can give.