Why is it a gray area? Compliance applies depending on what is posted. If a SN site for the bank advertises consumer loans, Reg Z applies, deposits, Reg DD applies.
Here is a list I have that I use when I teach on SN and compliance.
Risk mgmt (not a reg, but applicable.)
My opinions are not necessarily my employers.
Rules and Regs minus Relationships equals Resentment and Rebellion. John Maxwell