Frost proof hose bibs are code requirements in most jurisdiction these days, even on the Gulf Coast, and for a good reason.
Contrary to what you may think, a standard hose bib is more likely to be the cause of frozen pipes in this area (Gulf Coast) and in relative moderate freezing temperatures (+/- 20 to 32 C), than a pipe in an attic (which rarely freeze here except when the temperatures stay in the low to mid teens (C) for more than 24 hours), and the house is unheated or unoccupied.
With most attic pipes between joists, and below the required R-30 insulation , the ambient temperature from the rooms below will generally protect attic pipes for most of our coldest winters