Something else that needs to be said here.

Those protection diodes dump to VCC.
Your VCC rail needs to be able to deal with that.
78XX regulators are series pass devices.
If the current in through the protection diodes exceeds the drain of the
rest of the system from the 5V rail, then the 78XX will shut down, and the
5V rail will rise, until the drain equals the input current.
This may take your 5V rail out of spec.

If you're going to dump ESD through these (or any other) diodes, then the
5V rail needs to be able to absorb that transient.  Your 5V rail's
impedance is NOT zero.

I've seen a very similar mistake done on a thermal printer.
The printhead is driven from a darlington array, with protection diodes,
that are tied to VCC.
(Don't ask me why, resistive elements seldom provide much "kick" when
turned off...)
Unfortunately, the printhead is powered from an unregulated supply, usually
about 9-12VDC
The VCC rail usually measures 5.24V on a normal AC line, and the 7805
regulator is cold.
When the printer prints though, it grounds the printhead through the
darlington array, and this makes the 7805 pop on and off during printing.

For some reason, they have a big problem with this printer crashing, and
burning up printheads.
The print head elements can only take a couple mS on-time before smoking.



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