Actually that's intentional because agreements can be rather long winded and look more out of place with the narrower area of the answer section. And it uses the same colors as the answer section of the form.
If you want to change it so it maintains the columns and looks somewhat like other questions change this portion of the snog_forms_form template...
Code:
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To this...
Code:
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That will give you something like this...
View attachment 2582
I suggest using the template modification system for that and using the actual code from the template (there are tabs in there that need to be in the 'Find' section). I wouldn't edit the main template itself.