Thanks for the ideas. I'd assumed I'd need custom javascript to hide the button but I don't have scripting knowhow to figure it out. Covering the submit button is an interesting way of hiding but I assume I'd still have to accompany this with javascript to honor the visibility rules.
I know it seems like odd behaviour but the form I'm creating is for managing general website inquiries and, depending on the inquiry-type, we have visibility set to ask additional inquiry-specific questions. One inquiry-type is for job applicants. Rather than the marketing department being the middle person, it makes the most sense for us to redirect those users to our two recruiting subsites, job application form and the recruiting group's direct email. (this is the typical canned email message we send to anyone asking about a job, after a marketing person has a chance to read/process their email in the general inbox.)