I think so, but that hasn't stopped it from being a popular way to gather data, or from often being the only source of data used in a paper. I get that internet surveys are dirt cheap and it's easy to get large number of responses, but you have to take the results with a such a massive boulder of salt that it seems more like a convenient way to churn out papers (or even an easy way to get a desired result) than a way to conduct actual worthwhile research.