I came across a Facebook app/tab for a brand that required that the person Like the brand before being able to submit the form. I'm used to normal "like-gates" in which a splash screen is shown saying you have to Like the brand before being allowed to fill out the form. However, in this specific case, the Like button was "step 4" on this particular form that didn't have a Like-gate.
Here's an example of the form:

download bmml source – Wireframes created with Balsamiq Mockups
This seems to go against some of the Like button guidelines; however, does anyone have any feedback on if this is 1) allowed and 2) something that is a good practice?
I have my personal thoughts on this practice; however, I am curious to know if anyone has any data or experience with this type of layout.