It is not just about viewing unsightly plastic, but also ingestion of plastic and chemicals associated with plastic such as phthalates and endocrine disruptors. While spoilage is in issue, so are the various health problems associated with plastic. While there are too many unstudied plastic associated chemicals to quantify the impact, a number of them are clearly associated with cancer, obesity and infertility.
This month's issue of National Geographic is devoted to the problem of plastic in the ocean and is worth a look.