What is the violation?
334.30 Securing and Supporting.
Nonmetallic-sheathed cable shall be secured by staples, cable ties, straps, hangers, or similar fittings designed and installed so as not to damage the cable at intervals not exceeding 1.4 m (41/2 ft) and within 300 mm (12 in.) of every cabinet, box, or fitting. Flat cables shall not be stapled on edge.
Main Entry: 1strap
Etymology: alteration of strop, from Middle English, band or loop of leather or rope, from Old English, thong for securing an oar, from Latin struppus band, strap, from Greek strophos twisted band, from strephein to twist
1 a : a narrow usually flat strip or thong of a flexible material and especially leather used for securing, holding together, or wrapping b : something made of a strap forming a loop <a boot strap> c : a strip of leather used for flogging d : STROP
NM looks like a strap to me.
Not saying I would do this, just saying I do not see it as the end of the world or a violation.
You can now start throwing rocks....