There is a callOnly flag for the widget that I really recommend people use. In brief there was a lot of debate over whether emails should be included at all, and the flag was the compromise. Some orgs, for example the EFF, will be promoting the call-only flag when they distribute the code.
I'm in the advocacy space and you aren't collecting enough information to deliver the emails to Congress, the web forms require many other pieces of information like a title (Mr./Mrs. etc) and often a phone number. Better to take off the email option than mislead the public that it will be delivered.
